From 7dd062f83552fa8ff96224c29d60bafc001d73d3 Mon Sep 17 00:00:00 2001
From: Xavier Morel <xmo@odoo.com>
Date: Tue, 2 May 2017 12:07:30 +0200
Subject: [PATCH] [FIX] P3: text model types

* remove references to basestring & unicode (use relevant pycompat
  helpers)
* remove some str calls (either entirely or replaced by relevant
  helper, either text or native)
* use better API to avoid unnecessary conversions
* remove some XML declarations in views
---
 addons/anonymization/models/anonymization.py  |  3 +-
 addons/base_import/models/base_import.py      |  6 +-
 addons/board/models/board.py                  |  3 +-
 addons/bus/controllers/main.py                |  6 +-
 addons/calendar/models/calendar.py            | 17 +++---
 addons/calendar/models/ir_attachment.py       |  6 +-
 addons/calendar/models/mail_message.py        |  4 +-
 addons/crm/wizard/base_partner_merge.py       |  2 +-
 addons/document/models/ir_attachment.py       | 13 -----
 addons/hw_escpos/escpos/escpos.py             |  4 +-
 addons/l10n_be_intrastat/wizard/xml_decl.py   | 23 ++++----
 addons/l10n_lu/scripts/tax2csv.py             |  9 ++-
 addons/mail/controllers/main.py               |  4 +-
 addons/mail/models/ir_model.py                |  3 +-
 addons/mail/models/mail_thread.py             | 27 +++++----
 .../models/authorize_request.py               |  2 +-
 .../payment_authorize/tests/test_authorize.py |  2 +-
 addons/product/models/product.py              |  2 +-
 addons/product/models/product_template.py     |  2 +-
 addons/stock/models/product.py                |  4 +-
 addons/survey/controllers/main.py             |  2 +-
 .../wizard/survey_email_compose_message.py    |  3 +-
 addons/utm/models/utm.py                      |  3 +-
 addons/web/controllers/main.py                |  4 +-
 addons/web_editor/controllers/main.py         |  4 +-
 addons/web_editor/models/ir_qweb.py           | 15 +++--
 addons/web_editor/models/ir_ui_view.py        |  2 +-
 addons/website/controllers/main.py            |  2 +-
 addons/website/models/ir_ui_view.py           |  2 +-
 addons/website/models/website.py              |  9 +--
 doc/_extensions/github_link.py                |  4 +-
 doc/_extensions/odoo_ext/translator.py        | 10 ++--
 odoo/addons/base/ir/ir_fields.py              | 10 ++--
 odoo/addons/base/ir/ir_model.py               |  9 +--
 odoo/addons/base/ir/ir_qweb/__init__.py       |  2 +-
 odoo/addons/base/ir/ir_qweb/fields.py         | 27 +++++----
 odoo/addons/base/ir/ir_qweb/ir_qweb.py        |  2 +-
 odoo/addons/base/ir/ir_qweb/qweb.py           | 55 +++++++++----------
 odoo/addons/base/ir/ir_translation.py         |  2 +-
 odoo/addons/base/ir/ir_ui_view.py             | 10 ++--
 odoo/addons/base/ir/ir_values.py              |  6 +-
 odoo/addons/base/module/module.py             |  2 +-
 odoo/addons/base/res/res_users.py             |  6 +-
 odoo/addons/base/tests/test_func.py           |  4 +-
 odoo/addons/base/tests/test_qweb.py           |  2 +-
 odoo/addons/base/tests/test_res_config.py     |  4 +-
 odoo/addons/test_impex/models.py              |  7 ++-
 odoo/addons/test_impex/tests/test_export.py   |  4 +-
 .../test_new_api/tests/test_new_fields.py     |  6 +-
 odoo/fields.py                                | 45 ++++++---------
 odoo/http.py                                  | 18 +++---
 odoo/loglevels.py                             | 19 ++++---
 odoo/models.py                                | 46 ++++++++--------
 odoo/osv/expression.py                        | 29 ++++------
 odoo/osv/orm.py                               |  2 +-
 odoo/service/db.py                            |  3 +-
 odoo/tools/__init__.py                        |  2 +-
 odoo/tools/appdirs.py                         |  9 +--
 odoo/tools/cache.py                           |  4 +-
 odoo/tools/config.py                          | 20 +++----
 odoo/tools/convert.py                         |  5 +-
 odoo/tools/misc.py                            |  8 +--
 odoo/tools/pycompat.py                        | 43 +++++++++++++++
 odoo/tools/safe_eval.py                       |  4 +-
 odoo/tools/test_reports.py                    | 29 +++++-----
 odoo/tools/translate.py                       | 31 +++++------
 odoo/tools/yaml_import.py                     | 19 +++----
 67 files changed, 359 insertions(+), 337 deletions(-)

diff --git a/addons/anonymization/models/anonymization.py b/addons/anonymization/models/anonymization.py
index 2d4fe1b17d2..a0c90382938 100644
--- a/addons/anonymization/models/anonymization.py
+++ b/addons/anonymization/models/anonymization.py
@@ -6,6 +6,7 @@ from operator import itemgetter
 
 from odoo import api, fields, models, _
 from odoo.exceptions import UserError
+from odoo.tools import pycompat
 
 FIELD_STATES = [('clear', 'Clear'), ('anonymized', 'Anonymized'), ('not_existing', 'Not Existing'), ('new', 'New')]
 ANONYMIZATION_HISTORY_STATE = [('started', 'Started'), ('done', 'Done'), ('in_exception', 'Exception occured')]
@@ -13,7 +14,7 @@ ANONYMIZATION_DIRECTION = [('clear -> anonymized', 'clear -> anonymized'), ('ano
 
 
 def group(lst, cols):
-    if isinstance(cols, basestring):
+    if isinstance(cols, pycompat.string_types):
         cols = [cols]
     return dict((k, [v for v in itr]) for k, itr in groupby(sorted(lst, key=itemgetter(*cols)), itemgetter(*cols)))
 
diff --git a/addons/base_import/models/base_import.py b/addons/base_import/models/base_import.py
index e707beecc17..f2bab8b52b3 100644
--- a/addons/base_import/models/base_import.py
+++ b/addons/base_import/models/base_import.py
@@ -208,9 +208,9 @@ class Import(models.TransientModel):
                 if cell.ctype is xlrd.XL_CELL_NUMBER:
                     is_float = cell.value % 1 != 0.0
                     values.append(
-                        unicode(cell.value)
+                        pycompat.text_type(cell.value)
                         if is_float
-                        else unicode(int(cell.value))
+                        else pycompat.text_type(int(cell.value))
                     )
                 elif cell.ctype is xlrd.XL_CELL_DATE:
                     is_datetime = cell.value % 1 != 0.0
@@ -653,7 +653,7 @@ class Import(models.TransientModel):
         except ValueError as error:
             return [{
                 'type': 'error',
-                'message': unicode(error),
+                'message': pycompat.text_type(error),
                 'record': False,
             }]
 
diff --git a/addons/board/models/board.py b/addons/board/models/board.py
index 3acd277826a..81e849af263 100644
--- a/addons/board/models/board.py
+++ b/addons/board/models/board.py
@@ -2,6 +2,7 @@
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 
 from odoo import api, models
+from odoo.tools import pycompat
 
 
 class Board(models.AbstractModel):
@@ -45,7 +46,7 @@ class Board(models.AbstractModel):
             return node
 
         def encode(s):
-            if isinstance(s, unicode):
+            if isinstance(s, pycompat.text_type):
                 return s.encode('utf8')
             return s
 
diff --git a/addons/bus/controllers/main.py b/addons/bus/controllers/main.py
index 40118764751..4e82116e7c7 100644
--- a/addons/bus/controllers/main.py
+++ b/addons/bus/controllers/main.py
@@ -4,6 +4,8 @@ from odoo import exceptions
 from odoo.http import Controller, request, route
 from odoo.addons.bus.models.bus import dispatch
 
+from odoo.tools import pycompat
+
 
 class BusController(Controller):
     """ Examples:
@@ -14,7 +16,7 @@ class BusController(Controller):
 
     @route('/longpolling/send', type="json", auth="public")
     def send(self, channel, message):
-        if not isinstance(channel, basestring):
+        if not isinstance(channel, pycompat.string_types):
             raise Exception("bus.Bus only string channels are allowed.")
         return request.env['bus.bus'].sendone(channel, message)
 
@@ -33,7 +35,7 @@ class BusController(Controller):
             options = {}
         if not dispatch:
             raise Exception("bus.Bus unavailable")
-        if [c for c in channels if not isinstance(c, basestring)]:
+        if [c for c in channels if not isinstance(c, pycompat.string_types)]:
             raise Exception("bus.Bus only string channels are allowed.")
         if request.registry.in_test_mode():
             raise exceptions.UserError("bus.Bus not available in test mode")
diff --git a/addons/calendar/models/calendar.py b/addons/calendar/models/calendar.py
index b0c16c15b5a..a6656af1a5b 100644
--- a/addons/calendar/models/calendar.py
+++ b/addons/calendar/models/calendar.py
@@ -34,7 +34,7 @@ def calendar_id2real_id(calendar_id=None, with_date=False):
         :param with_date: if a value is passed to this param it will return dates based on value of withdate + calendar_id
         :return: real event id
     """
-    if calendar_id and isinstance(calendar_id, (basestring)):
+    if calendar_id and isinstance(calendar_id, pycompat.string_types):
         res = [bit for bit in calendar_id.split('-') if bit]
         if len(res) == 2:
             real_id = res[0]
@@ -48,7 +48,7 @@ def calendar_id2real_id(calendar_id=None, with_date=False):
 
 
 def get_real_ids(ids):
-    if isinstance(ids, (basestring, pycompat.integer_types)):
+    if isinstance(ids, (pycompat.string_types, pycompat.integer_types)):
         return calendar_id2real_id(ids)
 
     if isinstance(ids, (list, tuple)):
@@ -1060,7 +1060,7 @@ class Meeting(models.Model):
                 pile.reverse()
                 new_pile = []
                 for item in pile:
-                    if not isinstance(item, basestring):
+                    if not isinstance(item, pycompat.string_types):
                         res = item
                     elif str(item) == str('&'):
                         first = new_pile.pop()
@@ -1209,7 +1209,7 @@ class Meeting(models.Model):
 
         if interval == 'day':
             # Day number (1-31)
-            result = unicode(date.day)
+            result = pycompat.text_type(date.day)
 
         elif interval == 'month':
             # Localized month name and year
@@ -1221,6 +1221,7 @@ class Meeting(models.Model):
 
         elif interval == 'time':
             # Localized time
+            # FIXME: formats are specifically encoded to bytes, maybe use babel?
             dummy, format_time = self._get_date_formats()
             result = tools.ustr(date.strftime(format_time + " %Z"))
 
@@ -1316,7 +1317,7 @@ class Meeting(models.Model):
     @api.returns('self', lambda value: value.id)
     def message_post(self, **kwargs):
         thread_id = self.id
-        if isinstance(self.id, basestring):
+        if isinstance(self.id, pycompat.string_types):
             thread_id = get_real_ids(self.id)
         if self.env.context.get('default_date'):
             context = dict(self.env.context)
@@ -1352,7 +1353,7 @@ class Meeting(models.Model):
         for arg in args:
             if arg[0] == 'id':
                 for n, calendar_id in enumerate(arg[2]):
-                    if isinstance(calendar_id, basestring):
+                    if isinstance(calendar_id, pycompat.string_types):
                         arg[2][n] = calendar_id.split('-')[0]
         return super(Meeting, self)._name_search(name=name, args=args, operator=operator, limit=limit, name_get_uid=name_get_uid)
 
@@ -1390,7 +1391,7 @@ class Meeting(models.Model):
             # set end_date for calendar searching
             if any(field in values for field in ['recurrency', 'end_type', 'count', 'rrule_type', 'start', 'stop']):
                 for real_meeting in real_meetings:
-                    if real_meeting.recurrency and real_meeting.end_type in ('count', unicode('count')):
+                    if real_meeting.recurrency and real_meeting.end_type == u'count':
                         final_date = real_meeting._get_recurrency_end_date()
                         super(Meeting, real_meeting).write({'final_date': final_date})
 
@@ -1474,7 +1475,7 @@ class Meeting(models.Model):
         for calendar_id, real_id in select:
             res = real_data[real_id].copy()
             ls = calendar_id2real_id(calendar_id, with_date=res and res.get('duration', 0) > 0 and res.get('duration') or 1)
-            if not isinstance(ls, (basestring, pycompat.integer_types)) and len(ls) >= 2:
+            if not isinstance(ls, (pycompat.string_types, pycompat.integer_types)) and len(ls) >= 2:
                 res['start'] = ls[1]
                 res['stop'] = ls[2]
 
diff --git a/addons/calendar/models/ir_attachment.py b/addons/calendar/models/ir_attachment.py
index c98242db7e7..ae734ec59f4 100644
--- a/addons/calendar/models/ir_attachment.py
+++ b/addons/calendar/models/ir_attachment.py
@@ -5,6 +5,8 @@ from odoo import api, models
 
 from odoo.addons.calendar.models.calendar import get_real_ids
 
+from odoo.tools import pycompat
+
 
 class Attachment(models.Model):
 
@@ -16,13 +18,13 @@ class Attachment(models.Model):
         args = list(args)
         if any([leaf for leaf in args if leaf[0] == "res_model" and leaf[2] == 'calendar.event']):
             for index in range(len(args)):
-                if args[index][0] == "res_id" and isinstance(args[index][2], basestring):
+                if args[index][0] == "res_id" and isinstance(args[index][2], pycompat.string_types):
                     args[index] = (args[index][0], args[index][1], get_real_ids(args[index][2]))
         return super(Attachment, self).search(args, offset=offset, limit=limit, order=order, count=count)
 
     @api.multi
     def write(self, vals):
         """ When posting an attachment (new or not), convert the virtual ids in real ids. """
-        if isinstance(vals.get('res_id'), basestring):
+        if isinstance(vals.get('res_id'), pycompat.string_types):
             vals['res_id'] = get_real_ids(vals.get('res_id'))
         return super(Attachment, self).write(vals)
diff --git a/addons/calendar/models/mail_message.py b/addons/calendar/models/mail_message.py
index 0dc4d24e364..26be5080ab5 100644
--- a/addons/calendar/models/mail_message.py
+++ b/addons/calendar/models/mail_message.py
@@ -5,6 +5,8 @@ from odoo import api, models
 
 from odoo.addons.calendar.models.calendar import get_real_ids
 
+from odoo.tools import pycompat
+
 
 class Message(models.Model):
 
@@ -16,7 +18,7 @@ class Message(models.Model):
         args = list(args)
         for index in range(len(args)):
             if args[index][0] == "res_id":
-                if isinstance(args[index][2], basestring):
+                if isinstance(args[index][2], pycompat.string_types):
                     args[index] = (args[index][0], args[index][1], get_real_ids(args[index][2]))
                 elif isinstance(args[index][2], list):
                     args[index] = (args[index][0], args[index][1], [get_real_ids(x) for x in args[index][2]])
diff --git a/addons/crm/wizard/base_partner_merge.py b/addons/crm/wizard/base_partner_merge.py
index 7751e0106ed..24a573ad871 100644
--- a/addons/crm/wizard/base_partner_merge.py
+++ b/addons/crm/wizard/base_partner_merge.py
@@ -39,7 +39,7 @@ def html_entity_decode(string):
 
 
 def sanitize_email(email):
-    assert isinstance(email, basestring) and email
+    assert isinstance(email, pycompat.string_types) and email
 
     result = re.subn(r';|/|:', ',', html_entity_decode(email or ''))[0].split(',')
 
diff --git a/addons/document/models/ir_attachment.py b/addons/document/models/ir_attachment.py
index eff40db5df4..7e1afe36e4e 100644
--- a/addons/document/models/ir_attachment.py
+++ b/addons/document/models/ir_attachment.py
@@ -11,19 +11,6 @@ from odoo import api, models
 _logger = logging.getLogger(__name__)
 FTYPES = ['docx', 'pptx', 'xlsx', 'opendoc', 'pdf']
 
-# Keep function in case it is necessary to do toUnicode(buf.encode('ascii', 'replace'))
-def toUnicode(s):
-    try:
-        return s.decode('utf-8')
-    except UnicodeError:
-        try:
-            return s.decode('latin')
-        except UnicodeError:
-            try:
-                return s.encode('ascii')
-            except UnicodeError:
-                return s
-
 def textToString(element):
     buff = u""
     for node in element.childNodes:
diff --git a/addons/hw_escpos/escpos/escpos.py b/addons/hw_escpos/escpos/escpos.py
index e50537e0eeb..f076778ca9c 100644
--- a/addons/hw_escpos/escpos/escpos.py
+++ b/addons/hw_escpos/escpos/escpos.py
@@ -12,6 +12,8 @@ from hashlib import md5
 from PIL import Image
 from xml.etree import ElementTree as ET
 
+from odoo.tools import pycompat
+
 try:
     import jcconv
 except ImportError:
@@ -27,7 +29,7 @@ from .exceptions import *
 
 def utfstr(stuff):
     """ converts stuff to string and does without failing if stuff is a utf8 string """
-    if isinstance(stuff,basestring):
+    if isinstance(stuff,pycompat.string_types):
         return stuff
     else:
         return str(stuff)
diff --git a/addons/l10n_be_intrastat/wizard/xml_decl.py b/addons/l10n_be_intrastat/wizard/xml_decl.py
index f7d01db30d1..b5486d963c9 100644
--- a/addons/l10n_be_intrastat/wizard/xml_decl.py
+++ b/addons/l10n_be_intrastat/wizard/xml_decl.py
@@ -6,6 +6,7 @@ from xml.etree import ElementTree as ET
 from collections import namedtuple
 
 from odoo import api, exceptions, fields, models, _
+from odoo.tools.pycompat import text_type
 
 INTRASTAT_XMLNS = 'http://www.onegate.eu/2010-01-01'
 
@@ -264,18 +265,18 @@ class XmlDeclaration(models.TransientModel):
                 continue
             numlgn += 1
             item = ET.SubElement(datas, 'Item')
-            self._set_Dim(item, 'EXSEQCODE', unicode(numlgn))
-            self._set_Dim(item, 'EXTRF', unicode(linekey.EXTRF))
-            self._set_Dim(item, 'EXCNT', unicode(linekey.EXCNT))
-            self._set_Dim(item, 'EXTTA', unicode(linekey.EXTTA))
-            self._set_Dim(item, 'EXREG', unicode(linekey.EXREG))
-            self._set_Dim(item, 'EXTGO', unicode(linekey.EXGO))
+            self._set_Dim(item, 'EXSEQCODE', text_type(numlgn))
+            self._set_Dim(item, 'EXTRF', text_type(linekey.EXTRF))
+            self._set_Dim(item, 'EXCNT', text_type(linekey.EXCNT))
+            self._set_Dim(item, 'EXTTA', text_type(linekey.EXTTA))
+            self._set_Dim(item, 'EXREG', text_type(linekey.EXREG))
+            self._set_Dim(item, 'EXTGO', text_type(linekey.EXGO))
             if extendedmode:
-                self._set_Dim(item, 'EXTPC', unicode(linekey.EXTPC))
-                self._set_Dim(item, 'EXDELTRM', unicode(linekey.EXDELTRM))
-            self._set_Dim(item, 'EXTXVAL', unicode(round(amounts[0], 0)).replace(".", ","))
-            self._set_Dim(item, 'EXWEIGHT', unicode(round(amounts[1], 0)).replace(".", ","))
-            self._set_Dim(item, 'EXUNITS', unicode(round(amounts[2], 0)).replace(".", ","))
+                self._set_Dim(item, 'EXTPC', text_type(linekey.EXTPC))
+                self._set_Dim(item, 'EXDELTRM', text_type(linekey.EXDELTRM))
+            self._set_Dim(item, 'EXTXVAL', text_type(round(amounts[0], 0)).replace(".", ","))
+            self._set_Dim(item, 'EXWEIGHT', text_type(round(amounts[1], 0)).replace(".", ","))
+            self._set_Dim(item, 'EXUNITS', text_type(round(amounts[2], 0)).replace(".", ","))
 
         if numlgn == 0:
             #no datas
diff --git a/addons/l10n_lu/scripts/tax2csv.py b/addons/l10n_lu/scripts/tax2csv.py
index 9993272573f..013df32e3d3 100644
--- a/addons/l10n_lu/scripts/tax2csv.py
+++ b/addons/l10n_lu/scripts/tax2csv.py
@@ -5,12 +5,11 @@ import xlrd
 from odoo.tools import pycompat
 
 def _e(s):
-    if type(s) is unicode:
-        return s.encode('utf8')
-    elif s is None:
+    if s is None:
         return ''
-    else:
-        return str(s)
+    if pycompat.PY2 and type(s) == pycompat.text_type:
+        return s.encode('utf8')
+    return str(s)
 
 
 def _is_true(s):
diff --git a/addons/mail/controllers/main.py b/addons/mail/controllers/main.py
index 74f326d19fb..52ea655c078 100644
--- a/addons/mail/controllers/main.py
+++ b/addons/mail/controllers/main.py
@@ -13,7 +13,7 @@ from odoo import api, http, registry, SUPERUSER_ID, _
 from odoo.addons.web.controllers.main import binary_content
 from odoo.exceptions import AccessError
 from odoo.http import request
-from odoo.tools import consteq
+from odoo.tools import consteq, pycompat
 
 _logger = logging.getLogger(__name__)
 
@@ -182,7 +182,7 @@ class MailController(http.Controller):
             else:
                 # either a wrong message_id, either someone trying ids -> just go to messaging
                 return self._redirect_to_messaging()
-        elif res_id and isinstance(res_id, basestring):
+        elif res_id and isinstance(res_id, pycompat.string_types):
             res_id = int(res_id)
 
         return self._redirect_to_record(model, res_id, access_token)
diff --git a/addons/mail/models/ir_model.py b/addons/mail/models/ir_model.py
index e2231e38f5d..01862352e96 100644
--- a/addons/mail/models/ir_model.py
+++ b/addons/mail/models/ir_model.py
@@ -3,6 +3,7 @@
 
 from odoo import _, api, fields, models
 from odoo.exceptions import UserError
+from odoo.tools import pycompat
 
 
 class IrModel(models.Model):
@@ -41,7 +42,7 @@ class IrModel(models.Model):
         model_class = super(IrModel, self)._instanciate(model_data)
         if model_data.get('is_mail_thread') and model_class._name != 'mail.thread':
             parents = model_class._inherit or []
-            parents = [parents] if isinstance(parents, basestring) else parents
+            parents = [parents] if isinstance(parents, pycompat.string_types) else parents
             model_class._inherit = parents + ['mail.thread']
         return model_class
 
diff --git a/addons/mail/models/mail_thread.py b/addons/mail/models/mail_thread.py
index 35ae6d4ff9e..bc7b1d1072d 100644
--- a/addons/mail/models/mail_thread.py
+++ b/addons/mail/models/mail_thread.py
@@ -423,7 +423,7 @@ class MailThread(models.AbstractModel):
         for field_name, (template, post_kwargs) in pycompat.items(templates):
             if not template:
                 continue
-            if isinstance(template, basestring):
+            if isinstance(template, pycompat.string_types):
                 self.message_post_with_view(template, **post_kwargs)
             else:
                 self.message_post_with_template(template.id, **post_kwargs)
@@ -1268,12 +1268,15 @@ class MailThread(models.AbstractModel):
         # convert it to utf-8 for transport between the mailgate script and here.
         if isinstance(message, xmlrpclib.Binary):
             message = bytes(message.data)
-        # FIXME: message_from_string parses from a *native string*
-        # Warning: message_from_string doesn't always work correctly on unicode,
-        # we must use utf-8 strings here :-(
-        if isinstance(message, unicode):
+        # message_from_string parses from a *native string*, except apparently
+        # sometimes message is ISO-8859-1 binary data or some shit and the
+        # straightforward version (pycompat.to_native) won't work right ->
+        # always encode message to bytes then use the relevant method
+        # depending on ~python version
+        if isinstance(message, pycompat.text_type):
             message = message.encode('utf-8')
-        msg_txt = email.message_from_string(message)
+        extract = getattr(email, 'message_from_bytes', email.message_from_string)
+        msg_txt = extract(message)
 
         # parse the message, verify we are not in a loop by checking message_id is not duplicated
         msg = self.message_parse(msg_txt, save_original=save_original)
@@ -1494,9 +1497,9 @@ class MailThread(models.AbstractModel):
             'message_type': 'email',
         }
         if not isinstance(message, Message):
-            if isinstance(message, unicode):
-                # Warning: message_from_string doesn't always work correctly on unicode,
-                # we must use utf-8 strings here :-(
+            # message_from_string works on a native str, so on py2 we need to
+            # encode incoming unicode strings
+            if pycompat.PY2 and not isinstance(message, str):
                 message = message.encode('utf-8')
             message = email.message_from_string(message)
 
@@ -1725,11 +1728,11 @@ class MailThread(models.AbstractModel):
                 cid = info and info.get('cid')
             else:
                 continue
-            if isinstance(content, unicode):
+            if isinstance(content, pycompat.text_type):
                 content = content.encode('utf-8')
             data_attach = {
                 'name': name,
-                'datas': base64.b64encode(str(content)),
+                'datas': base64.b64encode(content),
                 'type': 'binary',
                 'datas_fname': name,
                 'description': name,
@@ -1922,7 +1925,7 @@ class MailThread(models.AbstractModel):
             values['slug'] = slug
         except ImportError:
             values['slug'] = lambda self: self.id
-        if isinstance(views_or_xmlid, basestring):
+        if isinstance(views_or_xmlid, pycompat.string_types):
             views = self.env.ref(views_or_xmlid, raise_if_not_found=False)
         else:
             views = views_or_xmlid
diff --git a/addons/payment_authorize/models/authorize_request.py b/addons/payment_authorize/models/authorize_request.py
index 0a00b1a4c70..7388a1a4329 100644
--- a/addons/payment_authorize/models/authorize_request.py
+++ b/addons/payment_authorize/models/authorize_request.py
@@ -58,7 +58,7 @@ class AuthorizeAPI():
 
         :param etree._Element data: etree data to process
         """
-        data = etree.tostring(data, xml_declaration=True, encoding='utf-8')
+        data = etree.tostring(data, encoding='utf-8')
         r = requests.post(self.url, data=data, headers={'Content-Type': 'text/xml'})
         r.raise_for_status()
         response = strip_ns(r.content, XMLNS)
diff --git a/addons/payment_authorize/tests/test_authorize.py b/addons/payment_authorize/tests/test_authorize.py
index b02d3d81209..668e17d0562 100644
--- a/addons/payment_authorize/tests/test_authorize.py
+++ b/addons/payment_authorize/tests/test_authorize.py
@@ -95,7 +95,7 @@ class AuthorizeForm(AuthorizeCommon):
             if values[1] in ['submit', 'x_fp_hash', 'return_url', 'x_state', 'x_ship_to_state']:
                 continue
             self.assertEqual(
-                unicode(values[2], "utf-8"),
+                values[2],
                 form_values[values[1]],
                 'Authorize: wrong value for input %s: received %s instead of %s' % (values[1], values[2], form_values[values[1]])
             )
diff --git a/addons/product/models/product.py b/addons/product/models/product.py
index 638e898aed8..c550e063709 100644
--- a/addons/product/models/product.py
+++ b/addons/product/models/product.py
@@ -158,7 +158,7 @@ class ProductProduct(models.Model):
             quantity = self._context.get('quantity', 1.0)
 
             # Support context pricelists specified as display_name or ID for compatibility
-            if isinstance(pricelist_id_or_name, basestring):
+            if isinstance(pricelist_id_or_name, pycompat.string_types):
                 pricelist_name_search = self.env['product.pricelist'].name_search(pricelist_id_or_name, operator='=', limit=1)
                 if pricelist_name_search:
                     pricelist = self.env['product.pricelist'].browse([pricelist_name_search[0][0]])
diff --git a/addons/product/models/product_template.py b/addons/product/models/product_template.py
index ccfbcf28b96..c9a2411f173 100644
--- a/addons/product/models/product_template.py
+++ b/addons/product/models/product_template.py
@@ -171,7 +171,7 @@ class ProductTemplate(models.Model):
             quantity = self._context.get('quantity', 1.0)
 
             # Support context pricelists specified as display_name or ID for compatibility
-            if isinstance(pricelist_id_or_name, basestring):
+            if isinstance(pricelist_id_or_name, pycompat.string_types):
                 pricelist_data = self.env['product.pricelist'].name_search(pricelist_id_or_name, operator='=', limit=1)
                 if pricelist_data:
                     pricelist = self.env['product.pricelist'].browse(pricelist_data[0][0])
diff --git a/addons/stock/models/product.py b/addons/stock/models/product.py
index 43cbe1e2e4d..693f5c0119e 100644
--- a/addons/stock/models/product.py
+++ b/addons/stock/models/product.py
@@ -161,7 +161,7 @@ class Product(models.Model):
         if self.env.context.get('location', False):
             if isinstance(self.env.context['location'], pycompat.integer_types):
                 location_ids = [self.env.context['location']]
-            elif isinstance(self.env.context['location'], basestring):
+            elif isinstance(self.env.context['location'], pycompat.string_types):
                 domain = [('complete_name', 'ilike', self.env.context['location'])]
                 if self.env.context.get('force_company', False):
                     domain += [('company_id', '=', self.env.context['force_company'])]
@@ -172,7 +172,7 @@ class Product(models.Model):
             if self.env.context.get('warehouse', False):
                 if isinstance(self.env.context['warehouse'], pycompat.integer_types):
                     wids = [self.env.context['warehouse']]
-                elif isinstance(self.env.context['warehouse'], basestring):
+                elif isinstance(self.env.context['warehouse'], pycompat.string_types):
                     domain = [('name', 'ilike', self.env.context['warehouse'])]
                     if self.env.context.get('force_company', False):
                         domain += [('company_id', '=', self.env.context['force_company'])]
diff --git a/addons/survey/controllers/main.py b/addons/survey/controllers/main.py
index 553fc5ad4b2..150503f07da 100644
--- a/addons/survey/controllers/main.py
+++ b/addons/survey/controllers/main.py
@@ -174,7 +174,7 @@ class WebsiteSurvey(http.Controller):
                     answer_tag = "%s_%s" % (answer_tag, 'comment')
                     answer_value = answer.value_text
                 elif answer.answer_type == 'number':
-                    answer_value = answer.value_number.__str__()
+                    answer_value = str(answer.value_number)
                 elif answer.answer_type == 'date':
                     answer_value = answer.value_date
                 elif answer.answer_type == 'suggestion' and not answer.value_suggested_row:
diff --git a/addons/survey/wizard/survey_email_compose_message.py b/addons/survey/wizard/survey_email_compose_message.py
index fb36d839c57..f23d836bc30 100644
--- a/addons/survey/wizard/survey_email_compose_message.py
+++ b/addons/survey/wizard/survey_email_compose_message.py
@@ -8,6 +8,7 @@ from werkzeug import urls
 
 from odoo import api, fields, models, _
 from odoo.exceptions import UserError
+from odoo.tools import pycompat
 
 emails_split = re.compile(r"[;,\n\r]+")
 email_validator = re.compile(r"[^@]+@[^@]+\.[^@]+")
@@ -119,7 +120,7 @@ class SurveyMailComposeMessage(models.TransientModel):
             if wizard.public != 'email_private':
                 return None
             else:
-                token = uuid.uuid4().__str__()
+                token = pycompat.text_type(uuid.uuid4())
                 # create response with token
                 survey_user_input = SurveyUserInput.create({
                     'survey_id': wizard.survey_id.id,
diff --git a/addons/utm/models/utm.py b/addons/utm/models/utm.py
index 5cb04d51425..b73329c1011 100644
--- a/addons/utm/models/utm.py
+++ b/addons/utm/models/utm.py
@@ -3,6 +3,7 @@
 
 from odoo import api, fields, models, SUPERUSER_ID
 from odoo.http import request
+from odoo.tools import pycompat
 
 
 class UtmMedium(models.Model):
@@ -72,7 +73,7 @@ class UtmMixin(models.AbstractModel):
                     # ir_http dispatch saves the url params in a cookie
                     value = request.httprequest.cookies.get(cookie_name)
                 # if we receive a string for a many2one, we search/create the id
-                if field.type == 'many2one' and isinstance(value, basestring) and value:
+                if field.type == 'many2one' and isinstance(value, pycompat.string_types) and value:
                     Model = self.env[field.comodel_name]
                     records = Model.search([('name', '=', value)], limit=1)
                     if not records:
diff --git a/addons/web/controllers/main.py b/addons/web/controllers/main.py
index 4efc3df9eec..9ac7b7a2fd8 100644
--- a/addons/web/controllers/main.py
+++ b/addons/web/controllers/main.py
@@ -1396,7 +1396,7 @@ class CSVExport(ExportFormat, http.Controller):
         for data in rows:
             row = []
             for d in data:
-                if isinstance(d, unicode):
+                if type(d) != str and isinstance(d, pycompat.string_types):
                     try:
                         d = d.encode('utf-8')
                     except UnicodeError:
@@ -1446,7 +1446,7 @@ class ExcelExport(ExportFormat, http.Controller):
         for row_index, row in enumerate(rows):
             for cell_index, cell_value in enumerate(row):
                 cell_style = base_style
-                if isinstance(cell_value, basestring):
+                if isinstance(cell_value, pycompat.string_types):
                     cell_value = re.sub("\r", " ", cell_value)
                 elif isinstance(cell_value, datetime.datetime):
                     cell_style = datetime_style
diff --git a/addons/web_editor/controllers/main.py b/addons/web_editor/controllers/main.py
index c501ce769d2..50a9540323a 100644
--- a/addons/web_editor/controllers/main.py
+++ b/addons/web_editor/controllers/main.py
@@ -39,7 +39,7 @@ class Web_Editor(http.Controller):
             debug=request.debug)
 
         for k in kwargs:
-            if isinstance(kwargs[k], basestring) and kwargs[k].isdigit():
+            if isinstance(kwargs[k], pycompat.string_types) and kwargs[k].isdigit():
                 kwargs[k] = int(kwargs[k])
 
         trans = dict(
@@ -186,7 +186,7 @@ class Web_Editor(http.Controller):
                 uploads += attachments.read(['name', 'mimetype', 'checksum', 'url'])
             except Exception as e:
                 logger.exception("Failed to upload image to attachment")
-                message = unicode(e)
+                message = pycompat.text_type(e)
 
         return """<script type='text/javascript'>
             window.parent['%s'](%s, %s);
diff --git a/addons/web_editor/models/ir_qweb.py b/addons/web_editor/models/ir_qweb.py
index cd665f38833..4b1cd512e06 100644
--- a/addons/web_editor/models/ir_qweb.py
+++ b/addons/web_editor/models/ir_qweb.py
@@ -48,7 +48,10 @@ class QWeb(models.AbstractModel):
         el.set('t-call', el.attrib.pop('t-snippet'))
         name = self.env['ir.ui.view'].search([('key', '=', el.attrib.get('t-call'))]).display_name
         thumbnail = el.attrib.pop('t-thumbnail', "oe-thumbnail")
-        div = u'<div name="%s" data-oe-type="snippet" data-oe-thumbnail="%s">' % (escape(ir_qweb.unicodifier(name)), escape(ir_qweb.unicodifier(thumbnail)))
+        div = u'<div name="%s" data-oe-type="snippet" data-oe-thumbnail="%s">' % (
+            escape(pycompat.to_text(name)),
+            escape(pycompat.to_text(thumbnail))
+        )
         return [self._append(ast.Str(div))] + self._compile_node(el, options) + [self._append(ast.Str(u'</div>'))]
 
     def _compile_directive_install(self, el, options):
@@ -58,7 +61,11 @@ class QWeb(models.AbstractModel):
                 return []
             name = el.attrib.get('string') or 'Snippet'
             thumbnail = el.attrib.pop('t-thumbnail', 'oe-thumbnail')
-            div = u'<div name="%s" data-oe-type="snippet" data-module-id="%s" data-oe-thumbnail="%s"><section/></div>' % (escape(ir_qweb.unicodifier(name)), module.id, escape(ir_qweb.unicodifier(thumbnail)))
+            div = u'<div name="%s" data-oe-type="snippet" data-module-id="%s" data-oe-thumbnail="%s"><section/></div>' % (
+                escape(pycompat.to_text(name)),
+                module.id,
+                escape(pycompat.to_text(thumbnail))
+            )
             return [self._append(ast.Str(div))]
         else:
             return []
@@ -202,7 +209,7 @@ class DateTime(models.AbstractModel):
     def attributes(self, record, field_name, options, values):
         attrs = super(DateTime, self).attributes(record, field_name, options, values)
         value = record[field_name]
-        if isinstance(value, basestring):
+        if isinstance(value, pycompat.string_types):
             value = fields.Datetime.from_string(value)
         if value:
             # convert from UTC (server timezone) to user timezone
@@ -326,7 +333,7 @@ class Image(models.AbstractModel):
 
         img = '<img class="%s" src="%s" style="%s"%s%s/>' % \
             (classes, src, options.get('style', ''), ' alt="%s"' % alt if alt else '', ' data-zoom="1" data-zoom-image="%s"' % src_zoom if src_zoom else '')
-        return ir_qweb.unicodifier(img)
+        return pycompat.to_text(img)
 
     local_url_re = re.compile(r'^/(?P<module>[^]]+)/static/(?P<rest>.+)$')
 
diff --git a/addons/web_editor/models/ir_ui_view.py b/addons/web_editor/models/ir_ui_view.py
index 7cf9e2f3a27..96c27bc923d 100644
--- a/addons/web_editor/models/ir_ui_view.py
+++ b/addons/web_editor/models/ir_ui_view.py
@@ -127,7 +127,7 @@ class IrUiView(models.Model):
 
     @api.model
     def _view_obj(self, view_id):
-        if isinstance(view_id, basestring):
+        if isinstance(view_id, pycompat.string_types):
             return self.env.ref(view_id)
         elif isinstance(view_id, pycompat.integer_types):
             return self.browse(view_id)
diff --git a/addons/website/controllers/main.py b/addons/website/controllers/main.py
index 2d758a3cc1f..229afc5c883 100644
--- a/addons/website/controllers/main.py
+++ b/addons/website/controllers/main.py
@@ -381,7 +381,7 @@ class Website(Home):
         action = action_id = None
 
         # find the action_id: either an xml_id, the path, or an ID
-        if isinstance(path_or_xml_id_or_id, basestring) and '.' in path_or_xml_id_or_id:
+        if isinstance(path_or_xml_id_or_id, pycompat.string_types) and '.' in path_or_xml_id_or_id:
             action = request.env.ref(path_or_xml_id_or_id, raise_if_not_found=False)
         if not action:
             action = ServerActions.search([('website_path', '=', path_or_xml_id_or_id), ('website_published', '=', True)], limit=1)
diff --git a/addons/website/models/ir_ui_view.py b/addons/website/models/ir_ui_view.py
index 7e956e85658..b5a3284d159 100644
--- a/addons/website/models/ir_ui_view.py
+++ b/addons/website/models/ir_ui_view.py
@@ -52,7 +52,7 @@ class View(models.Model):
 
     @api.model
     def _view_obj(self, view_id):
-        if isinstance(view_id, basestring):
+        if isinstance(view_id, pycompat.string_types):
             if 'website_id' in self._context:
                 domain = [('key', '=', view_id), '|', ('website_id', '=', False), ('website_id', '=', self._context.get('website_id'))]
                 order = 'website_id'
diff --git a/addons/website/models/website.py b/addons/website/models/website.py
index 0b407e4d753..c46e3c2a327 100644
--- a/addons/website/models/website.py
+++ b/addons/website/models/website.py
@@ -37,11 +37,8 @@ DEFAULT_CDN_FILTERS = [
 
 
 def url_for(path_or_uri, lang=None):
-    if isinstance(path_or_uri, unicode):
-        path_or_uri = path_or_uri.encode('utf-8')
-    current_path = request.httprequest.path
-    if isinstance(current_path, unicode):
-        current_path = current_path.encode('utf-8')
+    path_or_uri = pycompat.to_native(path_or_uri)
+    current_path = pycompat.to_native(request.httprequest.path)
     location = path_or_uri.strip()
     force_lang = lang is not None
     url = urls.url_parse(location)
@@ -667,7 +664,7 @@ class Menu(models.Model):
             self.browse(to_delete).unlink()
         for menu in data['data']:
             mid = menu['id']
-            if isinstance(mid, basestring):
+            if isinstance(mid, pycompat.string_types):
                 new_menu = self.create({'name': menu['name']})
                 replace_id(mid, new_menu.id)
         for menu in data['data']:
diff --git a/doc/_extensions/github_link.py b/doc/_extensions/github_link.py
index d3e5d61c28e..155e4083025 100644
--- a/doc/_extensions/github_link.py
+++ b/doc/_extensions/github_link.py
@@ -4,6 +4,8 @@ import os.path
 
 from werkzeug import urls
 
+from odoo.tools import pycompat
+
 """
 * adds github_link(mode) context variable: provides URL (in relevant mode) of
   current document on github
@@ -99,7 +101,7 @@ def add_doc_link(app, pagename, templatename, context, doctree):
     # in Sphinx 1.3 it's possible to have mutliple source suffixes and that
     # may be useful in the future
     source_suffix = app.config.source_suffix
-    source_suffix = source_suffix if isinstance(source_suffix, basestring) else source_suffix[0]
+    source_suffix = source_suffix if isinstance(source_suffix, pycompat.string_types) else source_suffix[0]
     # can't use functools.partial because 3rd positional is line not mode
     context['github_link'] = lambda mode='edit': make_github_link(
         app, 'doc/%s%s' % (pagename, source_suffix), mode=mode)
diff --git a/doc/_extensions/odoo_ext/translator.py b/doc/_extensions/odoo_ext/translator.py
index 3a1928364eb..443458f33c7 100644
--- a/doc/_extensions/odoo_ext/translator.py
+++ b/doc/_extensions/odoo_ext/translator.py
@@ -11,6 +11,8 @@ from docutils import nodes
 from sphinx import addnodes, util
 from sphinx.locale import admonitionlabels
 
+from odoo.tools import pycompat
+
 
 def _parents(node):
     while node.parent:
@@ -62,7 +64,7 @@ class BootstrapTranslator(nodes.NodeVisitor, object):
         self.param_separator = ','
 
     def encode(self, text):
-        return unicode(text).translate({
+        return pycompat.text_type(text).translate({
             ord('&'): u'&amp;',
             ord('<'): u'&lt;',
             ord('"'): u'&quot;',
@@ -71,7 +73,7 @@ class BootstrapTranslator(nodes.NodeVisitor, object):
         })
 
     def starttag(self, node, tagname, **attributes):
-        tagname = unicode(tagname).lower()
+        tagname = pycompat.text_type(tagname).lower()
 
         # extract generic attributes
         attrs = {name.lower(): value for name, value in attributes.items()}
@@ -105,8 +107,8 @@ class BootstrapTranslator(nodes.NodeVisitor, object):
         )
     # only "space characters" SPACE, CHARACTER TABULATION, LINE FEED,
     # FORM FEED and CARRIAGE RETURN should be collapsed, not al White_Space
-    def attval(self, value, whitespace=re.compile(u'[ \t\n\f\r]')):
-        return self.encode(whitespace.sub(u' ', unicode(value)))
+    def attval(self, value, whitespace=re.compile(u'[ \t\n\f\r]+')):
+        return self.encode(whitespace.sub(u' ', pycompat.text_type(value)))
 
     def astext(self):
         return u''.join(self.body)
diff --git a/odoo/addons/base/ir/ir_fields.py b/odoo/addons/base/ir/ir_fields.py
index 204d4599425..b8994d9221d 100644
--- a/odoo/addons/base/ir/ir_fields.py
+++ b/odoo/addons/base/ir/ir_fields.py
@@ -38,9 +38,9 @@ class IrFieldsConverter(models.AbstractModel):
     @api.model
     def _format_import_error(self, error_type, error_msg, error_params=(), error_args=None):
         # sanitize error params for later formatting by the import system
-        sanitize = lambda p: p.replace('%', '%%') if isinstance(p, basestring) else p
+        sanitize = lambda p: p.replace('%', '%%') if isinstance(p, pycompat.string_types) else p
         if error_params:
-            if isinstance(error_params, basestring):
+            if isinstance(error_params, pycompat.string_types):
                 error_params = sanitize(error_params)
             elif isinstance(error_params, dict):
                 error_params = {k: sanitize(v) for k, v in pycompat.items(error_params)}
@@ -78,7 +78,7 @@ class IrFieldsConverter(models.AbstractModel):
                 try:
                     converted[field], ws = converters[field](value)
                     for w in ws:
-                        if isinstance(w, basestring):
+                        if isinstance(w, pycompat.string_types):
                             # wrap warning string in an ImportWarning for
                             # uniform handling
                             w = ImportWarning(w)
@@ -269,14 +269,14 @@ class IrFieldsConverter(models.AbstractModel):
         for item, label in selection:
             label = ustr(label)
             labels = [label] + self._get_translations(('selection', 'model', 'code'), label)
-            if value == unicode(item) or value in labels:
+            if value == pycompat.text_type(item) or value in labels:
                 return item, []
 
         raise self._format_import_error(
             ValueError,
             _(u"Value '%s' not found in selection field '%%(field)s'"),
             value,
-            {'moreinfo': [_label or unicode(item) for item, _label in selection if _label or item]}
+            {'moreinfo': [_label or pycompat.text_type(item) for item, _label in selection if _label or item]}
         )
 
     @api.model
diff --git a/odoo/addons/base/ir/ir_model.py b/odoo/addons/base/ir/ir_model.py
index 4fa66406108..2092f4cd0b2 100644
--- a/odoo/addons/base/ir/ir_model.py
+++ b/odoo/addons/base/ir/ir_model.py
@@ -18,11 +18,6 @@ _logger = logging.getLogger(__name__)
 MODULE_UNINSTALL_FLAG = '_force_unlink'
 
 
-def encode(s):
-    """ Return an UTF8-encoded version of ``s``. """
-    return s.encode('utf8') if isinstance(s, unicode) else s
-
-
 # base environment for doing a safe_eval
 SAFE_EVAL_BASE = {
     'datetime': datetime,
@@ -272,7 +267,7 @@ class IrModel(models.Model):
     def _instanciate(self, model_data):
         """ Return a class for the custom model given by parameters ``model_data``. """
         class CustomModel(models.Model):
-            _name = encode(model_data['model'])
+            _name = pycompat.to_native(model_data['model'])
             _description = model_data['name']
             _module = False
             _custom = True
@@ -1134,7 +1129,7 @@ class IrModelAccess(models.Model):
             # User root have all accesses
             return True
 
-        assert isinstance(model, basestring), 'Not a model name: %s' % (model,)
+        assert isinstance(model, pycompat.string_types), 'Not a model name: %s' % (model,)
         assert mode in ('read', 'write', 'create', 'unlink'), 'Invalid access mode'
 
         # TransientModel records have no access rights, only an implicit access rule
diff --git a/odoo/addons/base/ir/ir_qweb/__init__.py b/odoo/addons/base/ir/ir_qweb/__init__.py
index b7fb78857b1..b0add281fdb 100644
--- a/odoo/addons/base/ir/ir_qweb/__init__.py
+++ b/odoo/addons/base/ir/ir_qweb/__init__.py
@@ -5,5 +5,5 @@ from . import fields
 from . import assetsbundle
 
 from .assetsbundle import AssetsBundle
-from .qweb import unicodifier, QWebException
+from .qweb import QWebException
 from .ir_qweb import IrQWeb, QWeb
diff --git a/odoo/addons/base/ir/ir_qweb/fields.py b/odoo/addons/base/ir/ir_qweb/fields.py
index 7e83fced25f..6cc5337f8a6 100644
--- a/odoo/addons/base/ir/ir_qweb/fields.py
+++ b/odoo/addons/base/ir/ir_qweb/fields.py
@@ -6,8 +6,7 @@ from io import BytesIO
 from odoo import api, fields, models, _
 from PIL import Image
 import babel
-from odoo.tools import html_escape as escape, posix_to_ldml, safe_eval, float_utils, format_date
-from .qweb import unicodifier
+from odoo.tools import html_escape as escape, posix_to_ldml, safe_eval, float_utils, format_date, pycompat
 
 import logging
 _logger = logging.getLogger(__name__)
@@ -20,7 +19,7 @@ def nl2br(string):
     :param str string:
     :rtype: unicode
     """
-    return unicodifier(string).replace(u'\n', u'<br>\n')
+    return pycompat.to_text(string).replace(u'\n', u'<br>\n')
 
 def html_escape(string, options):
     """ Automatically escapes content unless options['html-escape']
@@ -89,7 +88,7 @@ class FieldConverter(models.AbstractModel):
         Converts a single value to its HTML version/output
         :rtype: unicode
         """
-        return html_escape(unicodifier(value) or u'', options)
+        return html_escape(pycompat.to_text(value), options)
 
     @api.model
     def record_to_html(self, record, field_name, options):
@@ -124,7 +123,7 @@ class IntegerConverter(models.AbstractModel):
 
     @api.model
     def value_to_html(self, value, options):
-        return unicodifier(self.user_lang().format('%d', value, grouping=True).replace(r'-', u'\u2011'))
+        return pycompat.to_text(self.user_lang().format('%d', value, grouping=True).replace(r'-', u'\u2011'))
 
 
 class FloatConverter(models.AbstractModel):
@@ -153,7 +152,7 @@ class FloatConverter(models.AbstractModel):
         if precision is None:
             formatted = re.sub(r'(?:(0|\d+?)0+)$', r'\1', formatted)
 
-        return unicodifier(formatted)
+        return pycompat.to_text(formatted)
 
     @api.model
     def record_to_html(self, record, field_name, options):
@@ -183,7 +182,7 @@ class DateTimeConverter(models.AbstractModel):
         lang = self.user_lang()
         locale = babel.Locale.parse(lang.code)
 
-        if isinstance(value, basestring):
+        if isinstance(value, pycompat.string_types):
             value = fields.Datetime.from_string(value)
 
         value = fields.Datetime.context_timestamp(self, value)
@@ -201,7 +200,7 @@ class DateTimeConverter(models.AbstractModel):
         if options and options.get('hide_seconds'):
             pattern = pattern.replace(":ss", "").replace(":s", "")
 
-        return unicodifier(babel.dates.format_datetime(value, format=pattern, locale=locale))
+        return pycompat.to_text(babel.dates.format_datetime(value, format=pattern, locale=locale))
 
 
 class TextConverter(models.AbstractModel):
@@ -224,7 +223,7 @@ class SelectionConverter(models.AbstractModel):
     def value_to_html(self, value, options):
         if not value:
             return ''
-        return html_escape(unicodifier(options['selection'][value]) or u'', options)
+        return html_escape(pycompat.to_text(options['selection'][value]) or u'', options)
 
     @api.model
     def record_to_html(self, record, field_name, options):
@@ -253,7 +252,7 @@ class HTMLConverter(models.AbstractModel):
 
     @api.model
     def value_to_html(self, value, options):
-        return unicodifier(value) or u''
+        return pycompat.to_text(value)
 
 
 class ImageConverter(models.AbstractModel):
@@ -278,7 +277,7 @@ class ImageConverter(models.AbstractModel):
         except: # image.verify() throws "suitable exceptions", I have no idea what they are
             raise ValueError("Invalid image content")
 
-        return unicodifier(b'<img src="data:%s;base64,%s">' % (Image.MIME[image.format].encode('ascii'), value))
+        return u'<img src="data:%s;base64,%s">' % (Image.MIME[image.format], value.decode('ascii'))
 
 
 class MonetaryConverter(models.AbstractModel):
@@ -399,13 +398,13 @@ class RelativeDatetimeConverter(models.AbstractModel):
     def value_to_html(self, value, options):
         locale = babel.Locale.parse(self.user_lang().code)
 
-        if isinstance(value, basestring):
+        if isinstance(value, pycompat.string_types):
             value = fields.Datetime.from_string(value)
 
         # value should be a naive datetime in UTC. So is fields.Datetime.now()
         reference = fields.Datetime.from_string(options['now'])
 
-        return unicodifier(babel.dates.format_timedelta(value - reference, add_direction=True, locale=locale))
+        return pycompat.to_text(babel.dates.format_timedelta(value - reference, add_direction=True, locale=locale))
 
     @api.model
     def record_to_html(self, record, field_name, options):
@@ -482,4 +481,4 @@ class QwebView(models.AbstractModel):
 
         view = view.with_context(object=record)
 
-        return unicodifier(view.render(view._context, engine='ir.qweb'))
+        return pycompat.to_text(view.render(view._context, engine='ir.qweb'))
diff --git a/odoo/addons/base/ir/ir_qweb/ir_qweb.py b/odoo/addons/base/ir/ir_qweb/ir_qweb.py
index 102b36e0898..b23ab34f103 100644
--- a/odoo/addons/base/ir/ir_qweb/ir_qweb.py
+++ b/odoo/addons/base/ir/ir_qweb/ir_qweb.py
@@ -218,7 +218,7 @@ class IrQWeb(models.AbstractModel, QWeb):
         files = []
         remains = []
         for el in html.fragments_fromstring(template):
-            if isinstance(el, basestring):
+            if isinstance(el, pycompat.string_types):
                 remains.append(el)
             elif isinstance(el, html.HtmlElement):
                 href = el.get('href', '')
diff --git a/odoo/addons/base/ir/ir_qweb/qweb.py b/odoo/addons/base/ir/ir_qweb/qweb.py
index 69a01635f2d..61bd39eab8e 100644
--- a/odoo/addons/base/ir/ir_qweb/qweb.py
+++ b/odoo/addons/base/ir/ir_qweb/qweb.py
@@ -1,6 +1,7 @@
 # -*- coding: utf-8 -*-
 import ast
 import logging
+import os.path
 import re
 import traceback
 
@@ -176,13 +177,6 @@ class QWebException(Exception):
 # Avoid DeprecationWarning while still remaining compatible with werkzeug pre-0.9
 escape = (lambda text: _escape(text, quote=True)) if getattr(werkzeug, '__version__', '0.0') < '0.9.0' else _escape
 
-def unicodifier(val):
-    if val is None or val is False:
-        return u''
-    if isinstance(val, str):
-        return val.decode('utf-8')
-    return unicode(val)
-
 def foreach_iterator(base_ctx, enum, name):
     ctx = base_ctx.copy()
     if not enum:
@@ -380,10 +374,11 @@ class QWeb(object):
             if isinstance(document, etree._Element):
                 element = document
                 document = etree.tostring(document)
-            elif document.startswith("<?xml"):
-                element = etree.fromstring(document)
-            else:
+            elif os.path.exists(document):
                 element = etree.parse(document).getroot()
+            else:
+                element = etree.fromstring(document)
+
             for node in element:
                 if node.get('t-name') == str(template):
                     return (node, document)
@@ -527,12 +522,14 @@ class QWeb(object):
         * itertools
         Define:
         * escape
-        * unicodifier (empty string for a None or False, otherwise unicode string)
+        * to_text (empty string for a None or False, otherwise unicode string)
+        * string_types (replacement for basestring)
         """
         return ast.parse(dedent("""
             from collections import OrderedDict
             from odoo.tools import pycompat
-            from odoo.addons.base.ir.ir_qweb.qweb import escape, unicodifier, foreach_iterator
+            from odoo.tools.pycompat import to_text, string_types
+            from odoo.addons.base.ir.ir_qweb.qweb import escape, foreach_iterator
             """))
 
     def _create_def(self, options, body, prefix='fn', lineno=None):
@@ -777,7 +774,7 @@ class QWeb(object):
 
         if unqualified_el_tag == 't':
             return content
-        tag = u'<%s%s' % (el_tag, u''.join([u' %s="%s"' % (name, escape(unicodifier(value))) for name, value in pycompat.items(attrib)]))
+        tag = u'<%s%s' % (el_tag, u''.join([u' %s="%s"' % (name, escape(pycompat.to_text(value))) for name, value in pycompat.items(attrib)]))
         if unqualified_el_tag in self._void_elements:
             return [self._append(ast.Str(tag + '/>'))] + content
         else:
@@ -879,7 +876,7 @@ class QWeb(object):
             #         append(u' ')
             #         append(name)
             #         append(u'="')
-            #         append(escape(unicodifier((value)))
+            #         append(escape(to_text((value)))
             #         append(u'"')
             body.append(ast.For(
                 target=ast.Tuple(elts=[ast.Name(id='name', ctx=ast.Store()), ast.Name(id='value', ctx=ast.Store())], ctx=ast.Store()),
@@ -901,7 +898,7 @@ class QWeb(object):
                                 func=ast.Name(id='isinstance', ctx=ast.Load()),
                                 args=[
                                     ast.Name(id='value', ctx=ast.Load()),
-                                    ast.Name(id='basestring', ctx=ast.Load())
+                                    ast.Name(id='string_types', ctx=ast.Load())
                                 ],
                                 keywords=[],
                                 starargs=None, kwargs=None
@@ -915,7 +912,7 @@ class QWeb(object):
                         self._append(ast.Call(
                             func=ast.Name(id='escape', ctx=ast.Load()),
                             args=[ast.Call(
-                                func=ast.Name(id='unicodifier', ctx=ast.Load()),
+                                func=ast.Name(id='to_text', ctx=ast.Load()),
                                 args=[ast.Name(id='value', ctx=ast.Load())], keywords=[],
                                 starargs=None, kwargs=None
                             )], keywords=[],
@@ -955,7 +952,7 @@ class QWeb(object):
         if unqualified_el_tag == 't':
             return content
 
-        body = [self._append(ast.Str(u'<%s%s' % (el_tag, u''.join([u' %s="%s"' % (name, escape(unicodifier(value))) for name, value in pycompat.items(extra_attrib)]))))]
+        body = [self._append(ast.Str(u'<%s%s' % (el_tag, u''.join([u' %s="%s"' % (name, escape(pycompat.to_text(value))) for name, value in pycompat.items(extra_attrib)]))))]
         body.extend(self._compile_all_attributes(el, options, attr_already_created))
         if unqualified_el_tag in self._void_elements:
             body.append(self._append(ast.Str(u'/>')))
@@ -1044,7 +1041,7 @@ class QWeb(object):
     def _compile_directive_content(self, el, options):
         body = []
         if el.text is not None:
-            body.append(self._append(ast.Str(unicodifier(el.text))))
+            body.append(self._append(ast.Str(pycompat.to_text(el.text))))
         if el.getchildren():
             for item in el:
                 # ignore comments & processing instructions
@@ -1135,7 +1132,7 @@ class QWeb(object):
         )]
 
     def _compile_tail(self, el):
-        return el.tail is not None and [self._append(ast.Str(unicodifier(el.tail)))] or []
+        return el.tail is not None and [self._append(ast.Str(pycompat.to_text(el.tail)))] or []
 
     def _compile_directive_esc(self, el, options):
         field_options = self._compile_widget_options(el, 'esc')
@@ -1148,14 +1145,14 @@ class QWeb(object):
         return content + self._compile_widget_value(el, options)
 
     def _compile_widget(self, el, expression, field_options, escape=None):
-        # if isinstance(value, basestring):
-        #   value = escape(unicodifier(value))
+        # if isinstance(value, string_types):
+        #   value = escape(to_text(value))
         escaped = ast.If(
             test=ast.Call(
                 func=ast.Name(id='isinstance', ctx=ast.Load()),
                 args=[
                     ast.Name(id='content', ctx=ast.Load()),
-                    ast.Name(id='basestring', ctx=ast.Load())
+                    ast.Name(id='string_types', ctx=ast.Load())
                 ], keywords=[],
                 starargs=None, kwargs=None
             ),
@@ -1164,7 +1161,7 @@ class QWeb(object):
                 value=ast.Call(
                     func=ast.Name(id=escape, ctx=ast.Load()),
                     args=[ast.Call(
-                        func=ast.Name(id='unicodifier', ctx=ast.Load()),
+                        func=ast.Name(id='to_text', ctx=ast.Load()),
                         args=[ast.Name(id='content', ctx=ast.Load())], keywords=[],
                         starargs=None, kwargs=None
                     )], keywords=[],
@@ -1332,7 +1329,7 @@ class QWeb(object):
             ]
 
         # if content is not None:
-        #    display the tag (unicodifier(content))
+        #    display the tag (to_text(content))
         # else
         #    if default_content:
         #       display the tag with default content
@@ -1341,7 +1338,7 @@ class QWeb(object):
         return [self._if_content_is_not_Falsy(
             body=self._compile_tag(el, [self._append(
                 ast.Call(
-                    func=ast.Name(id='unicodifier', ctx=ast.Load()),
+                    func=ast.Name(id='to_text', ctx=ast.Load()),
                     args=[ast.Name(id='content', ctx=ast.Load())], keywords=[],
                     starargs=None, kwargs=None
                 )
@@ -1461,7 +1458,7 @@ class QWeb(object):
                 keys = []
                 values = []
                 for key, value in pycompat.items(options['nsmap']):
-                    if isinstance(key, basestring):
+                    if isinstance(key, pycompat.string_types):
                         keys.append(ast.Str(s=key))
                     elif key is None:
                         keys.append(ast.Name(id='None', ctx=ast.Load()))
@@ -1547,7 +1544,7 @@ class QWeb(object):
     def _compile_strexpr(self, expr):
         # ensure result is unicode
         return ast.Call(
-            func=ast.Name(id='unicodifier', ctx=ast.Load()),
+            func=ast.Name(id='to_text', ctx=ast.Load()),
             args=[self._compile_expr(expr)], keywords=[],
             starargs=None, kwargs=None
         )
@@ -1591,7 +1588,7 @@ class QWeb(object):
         for m in _FORMAT_REGEX.finditer(f):
             literal = f[base_idx:m.start()]
             if literal:
-                elts.append(ast.Str(literal if isinstance(literal, unicode) else literal.decode('utf-8')))
+                elts.append(ast.Str(literal if isinstance(literal, pycompat.text_type) else literal.decode('utf-8')))
 
             expr = m.group(1) or m.group(2)
             elts.append(self._compile_strexpr(expr))
@@ -1599,7 +1596,7 @@ class QWeb(object):
         # string past last regex match
         literal = f[base_idx:]
         if literal:
-            elts.append(ast.Str(literal if isinstance(literal, unicode) else literal.decode('utf-8')))
+            elts.append(ast.Str(literal if isinstance(literal, pycompat.text_type) else literal.decode('utf-8')))
 
         return reduce(lambda acc, it: ast.BinOp(
             left=acc,
diff --git a/odoo/addons/base/ir/ir_translation.py b/odoo/addons/base/ir/ir_translation.py
index cd954778a92..02c085818d2 100644
--- a/odoo/addons/base/ir/ir_translation.py
+++ b/odoo/addons/base/ir/ir_translation.py
@@ -394,7 +394,7 @@ class IrTranslation(models.Model):
         # always pass unicode so we can remove the string encoding/decoding.
         if not lang:
             return tools.ustr(source or '')
-        if isinstance(types, basestring):
+        if isinstance(types, pycompat.string_types):
             types = (types,)
         if res_id:
             if isinstance(res_id, pycompat.integer_types):
diff --git a/odoo/addons/base/ir/ir_ui_view.py b/odoo/addons/base/ir/ir_ui_view.py
index d70ee4cf951..1078d81b02f 100644
--- a/odoo/addons/base/ir/ir_ui_view.py
+++ b/odoo/addons/base/ir/ir_ui_view.py
@@ -29,7 +29,7 @@ from odoo.tools.convert import _fix_multiple_roots
 from odoo.tools.parse_version import parse_version
 from odoo.tools.safe_eval import safe_eval
 from odoo.tools.view_validation import valid_view
-from odoo.tools.translate import encode, xml_translate, TRANSLATED_ATTRS
+from odoo.tools.translate import xml_translate, TRANSLATED_ATTRS
 
 _logger = logging.getLogger(__name__)
 
@@ -233,7 +233,7 @@ actual arch.
                 else:
                     _logger.warning("View %s: Full path [%s] cannot be found.", view.xml_id, view.arch_fs)
                     arch_fs = False
-            view.arch = arch_fs or view.arch_db
+            view.arch = pycompat.to_text(arch_fs or view.arch_db)
 
     def _inverse_arch(self):
         for view in self:
@@ -269,7 +269,7 @@ actual arch.
             view.model_data_id = data['id']
 
     def _search_model_data_id(self, operator, value):
-        name = 'name' if isinstance(value, basestring) else 'id'
+        name = 'name' if isinstance(value, pycompat.string_types) else 'id'
         domain = [('model', '=', 'ir.ui.view'), (name, operator, value)]
         data = self.env['ir.model.data'].sudo().search(domain)
         return [('id', 'in', data.mapped('res_id'))]
@@ -313,7 +313,7 @@ actual arch.
         # Sanity checks: the view should not break anything upon rendering!
         # Any exception raised below will cause a transaction rollback.
         for view in self:
-            view_arch = etree.fromstring(encode(view.arch))
+            view_arch = etree.fromstring(view.arch.encode('utf-8'))
             view._valid_inheritance(view_arch)
             view_def = view.read_combined(['arch'])
             view_arch_utf8 = view_def['arch']
@@ -942,7 +942,7 @@ actual arch.
         arch_tree = etree.fromstring(arch)
         self.distribute_branding(arch_tree)
         root = E.templates(arch_tree)
-        arch = etree.tostring(root, encoding='utf-8', xml_declaration=True)
+        arch = etree.tostring(root, encoding='utf-8')
         return arch
 
     @api.model
diff --git a/odoo/addons/base/ir/ir_values.py b/odoo/addons/base/ir/ir_values.py
index ace2998b2b3..ebe1917da10 100644
--- a/odoo/addons/base/ir/ir_values.py
+++ b/odoo/addons/base/ir/ir_values.py
@@ -211,8 +211,8 @@ class IrValues(models.Model):
                                     match)
            :return: the newly created ir.values entry
         """
-        if isinstance(value, unicode):
-            value = value.encode('utf8')
+        if isinstance(value, pycompat.string_types):
+            value = pycompat.to_native(value)
         if company_id is True:
             # should be company-specific, need to get company id
             company_id = self.env.user.company_id.id
@@ -347,7 +347,7 @@ class IrValues(models.Model):
                               specific record of the model, not all records.
            :return: the newly created ir.values entry
         """
-        assert isinstance(action, basestring) and ',' in action, \
+        assert isinstance(action, pycompat.string_types) and ',' in action, \
                'Action definition must be an action reference, e.g. "ir.actions.act_window,42"'
         assert action_slot in ACTION_SLOTS, \
                'Action slot (%s) must be one of: %r' % (action_slot, ACTION_SLOTS)
diff --git a/odoo/addons/base/module/module.py b/odoo/addons/base/module/module.py
index e2f48e444a0..ccd4be8aa8b 100644
--- a/odoo/addons/base/module/module.py
+++ b/odoo/addons/base/module/module.py
@@ -645,7 +645,7 @@ class Module(models.Model):
                 updated_values = {}
                 for key in values:
                     old = getattr(mod, key)
-                    updated = tools.ustr(values[key]) if isinstance(values[key], basestring) else values[key]
+                    updated = tools.ustr(values[key]) if isinstance(values[key], pycompat.string_types) else values[key]
                     if (old or updated) and updated != old:
                         updated_values[key] = values[key]
                 if terp.get('installable', True) and mod.state == 'uninstallable':
diff --git a/odoo/addons/base/res/res_users.py b/odoo/addons/base/res/res_users.py
index 2a66c05a4aa..548e18e6879 100644
--- a/odoo/addons/base/res/res_users.py
+++ b/odoo/addons/base/res/res_users.py
@@ -107,7 +107,7 @@ class Groups(models.Model):
                 return expression.AND(domains)
             else:
                 return expression.OR(domains)
-        if isinstance(operand, basestring):
+        if isinstance(operand, pycompat.string_types):
             lst = False
             operand = [operand]
         where = []
@@ -306,7 +306,7 @@ class Users(models.Model):
 
     @api.model
     def read_group(self, domain, fields, groupby, offset=0, limit=None, orderby=False, lazy=True):
-        groupby_fields = set([groupby] if isinstance(groupby, basestring) else groupby)
+        groupby_fields = set([groupby] if isinstance(groupby, pycompat.string_types) else groupby)
         if groupby_fields.intersection(USER_PRIVATE_FIELDS):
             raise AccessError(_("Invalid 'group by' parameter"))
         return super(Users, self).read_group(domain, fields, groupby, offset=offset, limit=limit, orderby=orderby, lazy=lazy)
@@ -739,7 +739,7 @@ class GroupsView(models.Model):
             xml2.append({'class': "o_label_nowrap"})
             xml = E.field(E.group(*(xml1), col="2"), E.group(*(xml2), col="4"), name="groups_id", position="replace")
             xml.addprevious(etree.Comment("GENERATED AUTOMATICALLY BY GROUPS"))
-            xml_content = etree.tostring(xml, pretty_print=True, xml_declaration=True, encoding="utf-8")
+            xml_content = etree.tostring(xml, pretty_print=True, encoding="utf-8")
             view.with_context(lang=None).write({'arch': xml_content, 'arch_fs': False})
 
     def get_application_groups(self, domain):
diff --git a/odoo/addons/base/tests/test_func.py b/odoo/addons/base/tests/test_func.py
index ac394cb9b79..66ad02f4e9d 100644
--- a/odoo/addons/base/tests/test_func.py
+++ b/odoo/addons/base/tests/test_func.py
@@ -4,7 +4,7 @@
 import functools
 import unittest
 
-from odoo.tools import frozendict
+from odoo.tools import frozendict, pycompat
 from odoo.tools.func import compose
 
 
@@ -16,7 +16,7 @@ class TestCompose(unittest.TestCase):
     def test_decorator(self):
         """ ensure compose() can be partially applied as a decorator
         """
-        @functools.partial(compose, unicode)
+        @functools.partial(compose, pycompat.text_type)
         def mul(a, b):
             return a * b
 
diff --git a/odoo/addons/base/tests/test_qweb.py b/odoo/addons/base/tests/test_qweb.py
index 7a8f921af55..088949b3bd7 100644
--- a/odoo/addons/base/tests/test_qweb.py
+++ b/odoo/addons/base/tests/test_qweb.py
@@ -484,7 +484,7 @@ class FileSystemLoader(object):
             if node.get('t-name') == name:
                 root = etree.Element('templates')
                 root.append(deepcopy(node))
-                arch = etree.tostring(root, encoding='utf-8', xml_declaration=True)
+                arch = etree.tostring(root, encoding='utf-8')
                 return arch
 
 
diff --git a/odoo/addons/base/tests/test_res_config.py b/odoo/addons/base/tests/test_res_config.py
index 0be7dcc7c8d..1e30e1f1a24 100644
--- a/odoo/addons/base/tests/test_res_config.py
+++ b/odoo/addons/base/tests/test_res_config.py
@@ -46,7 +46,7 @@ class TestResConfig(TransactionCase):
         # Check types
         self.assertIsInstance(res, tuple)
         self.assertEqual(len(res), 2, "The result should contain 2 elements")
-        self.assertIsInstance(res[0], basestring)
+        self.assertIsInstance(res[0], pycompat.string_types)
         self.assertIsInstance(res[1], pycompat.integer_types)
 
         # Check returned values
@@ -58,7 +58,7 @@ class TestResConfig(TransactionCase):
         res = self.ResConfig.get_option_name(self.full_field_name)
 
         # Check type
-        self.assertIsInstance(res, basestring)
+        self.assertIsInstance(res, pycompat.string_types)
 
         # Check returned value
         self.assertEqual(res, self.expected_name)
diff --git a/odoo/addons/test_impex/models.py b/odoo/addons/test_impex/models.py
index f1e10b10abf..027739b2538 100644
--- a/odoo/addons/test_impex/models.py
+++ b/odoo/addons/test_impex/models.py
@@ -2,6 +2,7 @@
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 
 from odoo import api, fields, models
+from odoo.tools import pycompat
 
 
 def selection_fn(model):
@@ -48,7 +49,7 @@ for name, field in MODELS:
 
         @api.model
         def name_search(self, name='', args=None, operator='ilike', limit=100):
-            if isinstance(name, basestring) and name.split(':')[0] == self._name:
+            if isinstance(name, pycompat.string_types) and name.split(':')[0] == self._name:
                 records = self.search([('value', operator, int(name.split(':')[1]))])
                 return records.name_get()
             else:
@@ -70,7 +71,7 @@ class One2ManyChild(models.Model):
 
     @api.model
     def name_search(self, name='', args=None, operator='ilike', limit=100):
-        if isinstance(name, basestring) and name.split(':')[0] == self._name:
+        if isinstance(name, pycompat.string_types) and name.split(':')[0] == self._name:
             records = self.search([('value', operator, int(name.split(':')[1]))])
             return records.name_get()
         else:
@@ -124,7 +125,7 @@ class Many2ManyChild(models.Model):
 
     @api.model
     def name_search(self, name='', args=None, operator='ilike', limit=100):
-        if isinstance(name, basestring) and name.split(':')[0] == self._name:
+        if isinstance(name, pycompat.string_types) and name.split(':')[0] == self._name:
             records = self.search([('value', operator, int(name.split(':')[1]))])
             return records.name_get()
         else:
diff --git a/odoo/addons/test_impex/tests/test_export.py b/odoo/addons/test_impex/tests/test_export.py
index 72a3b2a6f75..9c7311319e8 100644
--- a/odoo/addons/test_impex/tests/test_export.py
+++ b/odoo/addons/test_impex/tests/test_export.py
@@ -69,7 +69,7 @@ class test_integer_field(CreatorCase):
     def test_huge(self):
         self.assertEqual(
             self.export(2**31-1),
-            [[unicode(2**31-1)]])
+            [[pycompat.text_type(2**31-1)]])
 
 
 class test_float_field(CreatorCase):
@@ -319,7 +319,7 @@ class test_m2o(CreatorCase):
         record = self.env['export.integer'].create({'value': 42})
         self.assertEqual(
             self.export(record.id, fields=['value/.id', 'value/value']),
-            [[unicode(record.id), u'42']])
+            [[pycompat.text_type(record.id), u'42']])
 
     def test_external_id(self):
         record = self.env['export.integer'].create({'value': 42})
diff --git a/odoo/addons/test_new_api/tests/test_new_fields.py b/odoo/addons/test_new_api/tests/test_new_fields.py
index 948470d60d6..b3fa31c77b8 100644
--- a/odoo/addons/test_new_api/tests/test_new_fields.py
+++ b/odoo/addons/test_new_api/tests/test_new_fields.py
@@ -5,7 +5,7 @@ from datetime import date, datetime
 
 from odoo.exceptions import AccessError, except_orm
 from odoo.tests import common
-from odoo.tools import mute_logger, float_repr
+from odoo.tools import mute_logger, float_repr, pycompat
 
 
 class TestFields(common.TransactionCase):
@@ -16,8 +16,8 @@ class TestFields(common.TransactionCase):
         discussion = self.env.ref('test_new_api.discussion_0')
 
         # read field as a record attribute or as a record item
-        self.assertIsInstance(discussion.name, basestring)
-        self.assertIsInstance(discussion['name'], basestring)
+        self.assertIsInstance(discussion.name, pycompat.string_types)
+        self.assertIsInstance(discussion['name'], pycompat.string_types)
         self.assertEqual(discussion['name'], discussion.name)
 
         # read it with method read()
diff --git a/odoo/fields.py b/odoo/fields.py
index 12702612d48..8efdd20b8fd 100644
--- a/odoo/fields.py
+++ b/odoo/fields.py
@@ -20,12 +20,11 @@ except ImportError:
 
 import psycopg2
 
-from odoo.sql_db import LazyCursor
-from odoo.tools import float_repr, float_round, frozendict, html_sanitize, human_size, pg_varchar, ustr, OrderedSet, pycompat
-from odoo.tools import DEFAULT_SERVER_DATE_FORMAT as DATE_FORMAT
-from odoo.tools import DEFAULT_SERVER_DATETIME_FORMAT as DATETIME_FORMAT
-from odoo.tools.translate import html_translate, _
-import odoo.tools.sql as sql
+from .sql_db import LazyCursor
+from .tools import float_repr, float_round, frozendict, html_sanitize, human_size, pg_varchar, ustr, OrderedSet, pycompat, sql
+from .tools import DEFAULT_SERVER_DATE_FORMAT as DATE_FORMAT
+from .tools import DEFAULT_SERVER_DATETIME_FORMAT as DATETIME_FORMAT
+from .tools.translate import html_translate, _
 
 DATE_LENGTH = len(date.today().strftime(DATE_FORMAT))
 DATETIME_LENGTH = len(datetime.now().strftime(DATETIME_FORMAT))
@@ -499,7 +498,7 @@ class Field(MetaField('DummyField', (object,), {})):
         def make_depends(deps):
             return tuple(deps(model) if callable(deps) else deps)
 
-        if isinstance(self.compute, basestring):
+        if isinstance(self.compute, pycompat.string_types):
             # if the compute method has been overridden, concatenate all their _depends
             self.depends = ()
             for method in resolve_mro(model, self.compute, callable):
@@ -518,7 +517,7 @@ class Field(MetaField('DummyField', (object,), {})):
     def _setup_related_full(self, model):
         """ Setup the attributes of a related field. """
         # fix the type of self.related if necessary
-        if isinstance(self.related, basestring):
+        if isinstance(self.related, pycompat.string_types):
             self.related = tuple(self.related.split('.'))
 
         # determine the chain of fields, and make sure they are all set up
@@ -746,9 +745,7 @@ class Field(MetaField('DummyField', (object,), {})):
         """ Convert ``value`` from the ``write`` format to the SQL format. """
         if value is None or value is False:
             return None
-        if isinstance(value, unicode):
-            return value.encode('utf8')
-        return str(value)
+        return pycompat.to_native(value)
 
     def convert_to_cache(self, value, record, validate=True):
         """ Convert ``value`` to the cache format; ``value`` may come from an
@@ -974,7 +971,7 @@ class Field(MetaField('DummyField', (object,), {})):
         for field in fields:
             for record in records:
                 record._cache[field] = field.convert_to_cache(False, record, validate=False)
-        if isinstance(self.compute, basestring):
+        if isinstance(self.compute, pycompat.string_types):
             getattr(records, self.compute)()
         else:
             self.compute(records)
@@ -1048,14 +1045,14 @@ class Field(MetaField('DummyField', (object,), {})):
 
     def determine_inverse(self, records):
         """ Given the value of ``self`` on ``records``, inverse the computation. """
-        if isinstance(self.inverse, basestring):
+        if isinstance(self.inverse, pycompat.string_types):
             getattr(records, self.inverse)()
         else:
             self.inverse(records)
 
     def determine_domain(self, records, operator, value):
         """ Return a domain representing a condition on ``self``. """
-        if isinstance(self.search, basestring):
+        if isinstance(self.search, pycompat.string_types):
             return getattr(records, self.search)(operator, value)
         else:
             return self.search(records, operator, value)
@@ -1510,7 +1507,7 @@ class Date(Field):
     def convert_to_cache(self, value, record, validate=True):
         if not value:
             return False
-        if isinstance(value, basestring):
+        if isinstance(value, pycompat.string_types):
             if validate:
                 # force parsing for validation
                 self.from_string(value)
@@ -1580,7 +1577,7 @@ class Datetime(Field):
     def convert_to_cache(self, value, record, validate=True):
         if not value:
             return False
-        if isinstance(value, basestring):
+        if isinstance(value, pycompat.string_types):
             if validate:
                 # force parsing for validation
                 self.from_string(value)
@@ -1736,7 +1733,7 @@ class Selection(Field):
             translated according to context language
         """
         selection = self.selection
-        if isinstance(selection, basestring):
+        if isinstance(selection, pycompat.string_types):
             return getattr(env[self.model_name], selection)()
         if callable(selection):
             return selection(env[self.model_name])
@@ -1753,7 +1750,7 @@ class Selection(Field):
     def get_values(self, env):
         """ return a list of the possible values """
         selection = self.selection
-        if isinstance(selection, basestring):
+        if isinstance(selection, pycompat.string_types):
             selection = getattr(env[self.model_name], selection)()
         elif callable(selection):
             selection = selection(env[self.model_name])
@@ -1777,14 +1774,6 @@ class Selection(Field):
                 return item[1]
         return False
 
-    def convert_to_column(self, value, record, values=None):
-        """ Convert ``value`` from the ``write`` format to the SQL format. """
-        if value is None or value is False:
-            return None
-        if isinstance(value, unicode):
-            return value.encode('utf8')
-        return str(value)
-
 
 class Reference(Selection):
     type = 'reference'
@@ -1802,7 +1791,7 @@ class Reference(Selection):
         if isinstance(value, BaseModel):
             if not validate or (value._name in self.get_values(record.env) and len(value) <= 1):
                 return process(value._name, value.id) if value else False
-        elif isinstance(value, basestring):
+        elif isinstance(value, pycompat.string_types):
             res_model, res_id = value.split(',')
             if record.env[res_model].browse(int(res_id)).exists():
                 return process(res_model, int(res_id))
@@ -2122,7 +2111,7 @@ class _RelationalMulti(_Relational):
             self.depends += tuple(
                 self.name + '.' + arg[0]
                 for arg in self.domain
-                if isinstance(arg, (tuple, list)) and isinstance(arg[0], basestring)
+                if isinstance(arg, (tuple, list)) and isinstance(arg[0], pycompat.string_types)
             )
 
 
diff --git a/odoo/http.py b/odoo/http.py
index 83cde441fb9..941fae06fe2 100644
--- a/odoo/http.py
+++ b/odoo/http.py
@@ -44,12 +44,12 @@ except ImportError:
     psutil = None
 
 import odoo
-from odoo.service.server import memory_info
-from odoo.service import security, model as service_model
-from odoo.tools.func import lazy_property
-from odoo.tools import ustr, consteq, frozendict, pycompat, unique
+from .service.server import memory_info
+from .service import security, model as service_model
+from .tools.func import lazy_property
+from .tools import ustr, consteq, frozendict, pycompat, unique
 
-from odoo.modules.module import module_manifest
+from .modules.module import module_manifest
 
 _logger = logging.getLogger(__name__)
 rpc_request = logging.getLogger(__name__ + '.rpc.request')
@@ -510,7 +510,7 @@ def route(route=None, **kw):
             if isinstance(response, Response) or f.routing_type == 'json':
                 return response
 
-            if isinstance(response, basestring):
+            if isinstance(response, pycompat.string_types):
                 return Response(response)
 
             if isinstance(response, werkzeug.exceptions.HTTPException):
@@ -1386,7 +1386,7 @@ class Root(object):
                 else:
                     raise
 
-        if isinstance(result, basestring):
+        if isinstance(result, pycompat.string_types):
             response = Response(result, mimetype='text/html')
         else:
             response = result
@@ -1554,7 +1554,7 @@ def send_file(filepath_or_fp, mimetype=None, as_attachment=False, filename=None,
 
     :param cache_timeout: the timeout in seconds for the headers.
     """
-    if isinstance(filepath_or_fp, (str, unicode)):
+    if isinstance(filepath_or_fp, pycompat.string_types):
         if not filename:
             filename = os.path.basename(filepath_or_fp)
         file = open(filepath_or_fp, 'rb')
@@ -1604,7 +1604,7 @@ def send_file(filepath_or_fp, mimetype=None, as_attachment=False, filename=None,
             mtime,
             size,
             adler32(
-                filename.encode('utf-8') if isinstance(filename, unicode)
+                filename.encode('utf-8') if isinstance(filename, pycompat.text_type)
                 else filename
             ) & 0xffffffff
         ))
diff --git a/odoo/loglevels.py b/odoo/loglevels.py
index 8c0242867d2..4380ff29427 100644
--- a/odoo/loglevels.py
+++ b/odoo/loglevels.py
@@ -37,13 +37,16 @@ def get_encodings(hint_encoding='utf-8'):
         if prefenc:
             yield prefenc
 
+# not using pycompat to avoid circular import: pycompat is in tools much of
+# which comes back to import loglevels
+text_type = type(u'')
 def ustr(value, hint_encoding='utf-8', errors='strict'):
     """This method is similar to the builtin `unicode`, except
     that it may try multiple encodings to find one that works
     for decoding `value`, and defaults to 'utf-8' first.
 
-    :param: value: the value to convert
-    :param: hint_encoding: an optional encoding that was detecte
+    :param value: the value to convert
+    :param hint_encoding: an optional encoding that was detecte
         upstream and should be tried first to decode ``value``.
     :param str errors: optional `errors` flag to pass to the unicode
         built-in to indicate how illegal character values should be
@@ -60,24 +63,24 @@ def ustr(value, hint_encoding='utf-8', errors='strict'):
     # cases faster (isinstance/issubclass are significantly slower)
     ttype = type(value)
 
-    if ttype is unicode:
+    if ttype is text_type:
         return value
 
     # special short-circuit for str, as we still needs to support
     # str subclasses such as `odoo.tools.unquote`
-    if ttype is str or issubclass(ttype, str):
+    if ttype is bytes or issubclass(ttype, bytes):
 
         # try hint_encoding first, avoids call to get_encoding()
         # for the most common case
         try:
-            return unicode(value, hint_encoding, errors=errors)
+            return value.decode(hint_encoding, errors=errors)
         except Exception:
             pass
 
         # rare: no luck with hint_encoding, attempt other ones
         for ln in get_encodings(hint_encoding):
             try:
-                return unicode(value, ln, errors=errors)
+                return value.decode(ln, errors=errors)
             except Exception:
                 pass
 
@@ -86,7 +89,7 @@ def ustr(value, hint_encoding='utf-8', errors='strict'):
 
     # fallback for non-string values
     try:
-        return unicode(value)
+        return text_type(value)
     except Exception:
         raise UnicodeError('unable to convert %r' % (value,))
 
@@ -95,6 +98,6 @@ def exception_to_unicode(e):
     if hasattr(e, 'args'):
         return "\n".join((ustr(a) for a in e.args))
     try:
-        return unicode(e)
+        return text_type(e)
     except Exception:
         return u"Unknown message"
diff --git a/odoo/models.py b/odoo/models.py
index dd55b799f0a..d8b693322c7 100644
--- a/odoo/models.py
+++ b/odoo/models.py
@@ -173,7 +173,7 @@ class NewId(object):
         return False
     __nonzero__ = __bool__
 
-IdType = pycompat.integer_types + (str, unicode, NewId)
+IdType = pycompat.integer_types + pycompat.string_types + (NewId,)
 
 
 # maximum number of prefetched records
@@ -184,6 +184,7 @@ LOG_ACCESS_COLUMNS = ['create_uid', 'create_date', 'write_uid', 'write_date']
 MAGIC_COLUMNS = ['id'] + LOG_ACCESS_COLUMNS
 
 
+@pycompat.implements_to_string
 class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
     """ Base class for Odoo models.
 
@@ -405,7 +406,7 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
 
         # determine inherited models
         parents = cls._inherit
-        parents = [parents] if isinstance(parents, basestring) else (parents or [])
+        parents = [parents] if isinstance(parents, pycompat.string_types) else (parents or [])
 
         # determine the model's name
         name = cls._name or (len(parents) == 1 and parents[0]) or cls.__name__
@@ -769,7 +770,7 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
                 # avoid broken transaction) and keep going
                 cr.execute('ROLLBACK TO SAVEPOINT model_load_save')
             except Exception as e:
-                message = (_('Unknown error during import:') + ' %s: %s' % (type(e), unicode(e)))
+                message = (_(u'Unknown error during import:') + u' %s: %s' % (type(e), e))
                 moreinfo = _('Resolve other errors first')
                 messages.append(dict(info, type='error', message=message, moreinfo=moreinfo))
                 # Failed for some reason, perhaps due to invalid data supplied,
@@ -886,7 +887,7 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
             # processing of response, but injects human readable in message
             exc_vals = dict(base, record=record, field=field_names[field])
             record = dict(base, type=type, record=record, field=field,
-                          message=unicode(exception.args[0]) % exc_vals)
+                          message=pycompat.text_type(exception.args[0]) % exc_vals)
             if len(exception.args) > 1 and exception.args[1]:
                 record.update(exception.args[1])
             log(record)
@@ -1714,7 +1715,7 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
         value = False if value is None else value
         gb = groupby_dict.get(key)
         if gb and gb['type'] in ('date', 'datetime') and value:
-            if isinstance(value, basestring):
+            if isinstance(value, pycompat.string_types):
                 dt_format = DEFAULT_SERVER_DATETIME_FORMAT if gb['type'] == 'datetime' else DEFAULT_SERVER_DATE_FORMAT
                 value = datetime.datetime.strptime(value, dt_format)
             if gb['tz_convert']:
@@ -1821,7 +1822,7 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
         """
         result = self._read_group_raw(domain, fields, groupby, offset=offset, limit=limit, orderby=orderby, lazy=lazy)
 
-        groupby = [groupby] if isinstance(groupby, basestring) else list(OrderedSet(groupby))
+        groupby = [groupby] if isinstance(groupby, pycompat.string_types) else list(OrderedSet(groupby))
         dt = [
             f for f in groupby
             if self._fields[f.split(':')[0]].type in ('date', 'datetime')
@@ -1845,7 +1846,7 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
         query = self._where_calc(domain)
         fields = fields or [f.name for f in pycompat.values(self._fields) if f.store]
 
-        groupby = [groupby] if isinstance(groupby, basestring) else list(OrderedSet(groupby))
+        groupby = [groupby] if isinstance(groupby, pycompat.string_types) else list(OrderedSet(groupby))
         groupby_list = groupby[:1] if lazy else groupby
         annotated_groupbys = [self._read_group_process_groupby(gb, query) for gb in groupby_list]
         groupby_fields = [g['field'] for g in annotated_groupbys]
@@ -4396,7 +4397,7 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
         """
         if not func:
             return self                 # support for an empty path of fields
-        if isinstance(func, basestring):
+        if isinstance(func, pycompat.string_types):
             recs = self
             for name in func.split('.'):
                 recs = recs._mapped_func(operator.itemgetter(name))
@@ -4421,7 +4422,7 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
 
             :param func: a function or a dot-separated sequence of field names
         """
-        if isinstance(func, basestring):
+        if isinstance(func, pycompat.string_types):
             name = func
             func = lambda rec: any(rec.mapped(name))
         return self.browse([rec.id for rec in self if func(rec)])
@@ -4438,7 +4439,7 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
         if key is None:
             recs = self.search([('id', 'in', self.ids)])
             return self.browse(reversed(recs._ids)) if reverse else recs
-        if isinstance(key, basestring):
+        if isinstance(key, pycompat.string_types):
             key = itemgetter(key)
         return self.browse(item.id for item in sorted(self, key=key, reverse=reverse))
 
@@ -4523,7 +4524,7 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
         """
         if isinstance(item, BaseModel) and self._name == item._name:
             return len(item) == 1 and item.id in self._ids
-        elif isinstance(item, basestring):
+        elif isinstance(item, pycompat.string_types):
             return item in self._fields
         else:
             raise TypeError("Mixing apples and oranges: %s in %s" % (item, self))
@@ -4616,11 +4617,8 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
 
     def __str__(self):
         return "%s%s" % (self._name, getattr(self, '_ids', ""))
-
-    def __unicode__(self):
-        return unicode(str(self))
-
-    __repr__ = __str__
+    def __repr__(self):
+        return str(self)
 
     def __hash__(self):
         if hasattr(self, '_ids'):
@@ -4640,7 +4638,7 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
                 rs = inst[10:20]            # subset of inst
                 nm = rs['name']             # name of first record in inst
         """
-        if isinstance(key, basestring):
+        if isinstance(key, pycompat.string_types):
             # important: one must call the field's getter
             return self._fields[key].__get__(self, type(self))
         elif isinstance(key, slice):
@@ -4983,7 +4981,7 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
 
         # At the moment, the client does not support updates on a *2many field
         # while this one is modified by the user.
-        if isinstance(field_name, basestring) and \
+        if isinstance(field_name, pycompat.string_types) and \
                 self._fields[field_name].type in ('one2many', 'many2many'):
             dirty.discard(field_name)
 
@@ -5008,13 +5006,13 @@ class RecordCache(MutableMapping):
 
     def contains(self, field):
         """ Return whether `records[0]` has a value for ``field`` in cache. """
-        if isinstance(field, basestring):
+        if isinstance(field, pycompat.string_types):
             field = self._recs._fields[field]
         return self._recs.id in self._recs.env.cache[field]
 
     def __contains__(self, field):
         """ Return whether `records[0]` has a regular value for ``field`` in cache. """
-        if isinstance(field, basestring):
+        if isinstance(field, pycompat.string_types):
             field = self._recs._fields[field]
         dummy = SpecialValue(None)
         value = self._recs.env.cache[field].get(self._recs.id, dummy)
@@ -5022,7 +5020,7 @@ class RecordCache(MutableMapping):
 
     def get(self, field, default=None):
         """ Return the cached, regular value of ``field`` for `records[0]`, or ``default``. """
-        if isinstance(field, basestring):
+        if isinstance(field, pycompat.string_types):
             field = self._recs._fields[field]
         dummy = SpecialValue(None)
         value = self._recs.env.cache[field].get(self._recs.id, dummy)
@@ -5030,14 +5028,14 @@ class RecordCache(MutableMapping):
 
     def __getitem__(self, field):
         """ Return the cached value of ``field`` for `records[0]`. """
-        if isinstance(field, basestring):
+        if isinstance(field, pycompat.string_types):
             field = self._recs._fields[field]
         value = self._recs.env.cache[field][self._recs.id]
         return value.get() if isinstance(value, SpecialValue) else value
 
     def __setitem__(self, field, value):
         """ Assign the cached value of ``field`` for all records in ``records``. """
-        if isinstance(field, basestring):
+        if isinstance(field, pycompat.string_types):
             field = self._recs._fields[field]
         values = dict.fromkeys(self._recs._ids, value)
         self._recs.env.cache[field].update(values)
@@ -5056,7 +5054,7 @@ class RecordCache(MutableMapping):
 
     def __delitem__(self, field):
         """ Remove the cached value of ``field`` for all ``records``. """
-        if isinstance(field, basestring):
+        if isinstance(field, pycompat.string_types):
             field = self._recs._fields[field]
         field_cache = self._recs.env.cache[field]
         for id in self._recs._ids:
diff --git a/odoo/osv/expression.py b/odoo/osv/expression.py
index 8df300a2bd4..c1363c4f06d 100644
--- a/odoo/osv/expression.py
+++ b/odoo/osv/expression.py
@@ -377,7 +377,7 @@ def normalize_leaf(element):
 
 def is_operator(element):
     """ Test whether an object is a valid domain operator. """
-    return isinstance(element, basestring) and element in DOMAIN_OPERATORS
+    return isinstance(element, pycompat.string_types) and element in DOMAIN_OPERATORS
 
 
 def is_leaf(element, internal=False):
@@ -398,7 +398,7 @@ def is_leaf(element, internal=False):
     return (isinstance(element, tuple) or isinstance(element, list)) \
         and len(element) == 3 \
         and element[1] in INTERNAL_OPS \
-        and ((isinstance(element[0], basestring) and element[0])
+        and ((isinstance(element[0], pycompat.string_types) and element[0])
              or tuple(element) in (TRUE_LEAF, FALSE_LEAF))
 
 
@@ -697,9 +697,9 @@ class expression(object):
                         return the list of related ids
             """
             names = []
-            if isinstance(value, basestring):
+            if isinstance(value, pycompat.string_types):
                 names = [value]
-            elif value and isinstance(value, (tuple, list)) and all(isinstance(item, basestring) for item in value):
+            elif value and isinstance(value, (tuple, list)) and all(isinstance(item, pycompat.string_types) for item in value):
                 names = value
             elif isinstance(value, pycompat.integer_types):
                 return [value]
@@ -925,7 +925,7 @@ class expression(object):
                     domain = domain(model)
                 is_integer_m2o = comodel._fields[field.inverse_name].type == 'integer'
                 if right is not False:
-                    if isinstance(right, basestring):
+                    if isinstance(right, pycompat.string_types):
                         op = {'!=': '=', 'not like': 'like', 'not ilike': 'ilike'}.get(operator, operator)
                         ids2 = [x[0] for x in comodel.name_search(right, domain or [], op, limit=None)]
                         if ids2:
@@ -993,7 +993,7 @@ class expression(object):
                 else:
                     call_null_m2m = True
                     if right is not False:
-                        if isinstance(right, basestring):
+                        if isinstance(right, pycompat.string_types):
                             op = {'!=': '=', 'not like': 'like', 'not ilike': 'ilike'}.get(operator, operator)
                             domain = field.domain
                             if callable(domain):
@@ -1051,8 +1051,8 @@ class expression(object):
                             res_ids.append(False)  # TODO this should not be appended if False was in 'right'
                         return left, 'in', res_ids
                     # resolve string-based m2o criterion into IDs
-                    if isinstance(right, basestring) or \
-                            right and isinstance(right, (tuple, list)) and all(isinstance(item, basestring) for item in right):
+                    if isinstance(right, pycompat.string_types) or \
+                            right and isinstance(right, (tuple, list)) and all(isinstance(item, pycompat.string_types) for item in right):
                         push(create_substitution_leaf(leaf, _get_expression(comodel, left, right, operator), model))
                     else:
                         # right == [] or right == False and all other cases are handled by __leaf_to_sql()
@@ -1263,21 +1263,16 @@ class expression(object):
 
             add_null = False
             if need_wildcard:
-                if isinstance(right, str):
-                    str_utf8 = right
-                elif isinstance(right, unicode):
-                    str_utf8 = right.encode('utf-8')
-                else:
-                    str_utf8 = str(right)
-                params = '%%%s%%' % str_utf8
-                add_null = not str_utf8
+                native_str = pycompat.to_native(right)
+                params = '%%%s%%' % native_str
+                add_null = not native_str
             elif left in model:
                 params = model._fields[left].convert_to_column(right, model)
 
             if add_null:
                 query = '(%s OR %s."%s" IS NULL)' % (query, table_alias, left)
 
-        if isinstance(params, basestring):
+        if isinstance(params, pycompat.string_types):
             params = [params]
         return query, params
 
diff --git a/odoo/osv/orm.py b/odoo/osv/orm.py
index e4be2706c7f..f189638582b 100644
--- a/odoo/osv/orm.py
+++ b/odoo/osv/orm.py
@@ -125,7 +125,7 @@ def setup_modifiers(node, field=None, context=None, in_tree_view=False):
 
 def test_modifiers(what, expected):
     modifiers = {}
-    if isinstance(what, basestring):
+    if isinstance(what, pycompat.string_types):
         node = etree.fromstring(what)
         transfer_node_to_modifiers(node, modifiers)
         simplify_modifiers(modifiers)
diff --git a/odoo/service/db.py b/odoo/service/db.py
index 861369b5b07..ce9483fedd7 100644
--- a/odoo/service/db.py
+++ b/odoo/service/db.py
@@ -23,6 +23,7 @@ import odoo.sql_db
 import odoo.tools
 from odoo.sql_db import db_connect
 from odoo.release import version_info
+from odoo.tools import pycompat
 
 _logger = logging.getLogger(__name__)
 
@@ -223,7 +224,7 @@ def exp_restore(db_name, data, copy=False):
     return True
 
 def restore_db(db, dump_file, copy=False):
-    assert isinstance(db, basestring)
+    assert isinstance(db, pycompat.string_types)
     if exp_db_exist(db):
         _logger.info('RESTORE DB: %s already exists', db)
         raise Exception("Database already exists")
diff --git a/odoo/tools/__init__.py b/odoo/tools/__init__.py
index 13c2fd410b9..2b4eeb50c55 100644
--- a/odoo/tools/__init__.py
+++ b/odoo/tools/__init__.py
@@ -1,7 +1,7 @@
 # -*- coding: utf-8 -*-
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 
-import copy
+from . import pycompat
 from . import win32
 from . import appdirs
 from .config import config
diff --git a/odoo/tools/appdirs.py b/odoo/tools/appdirs.py
index 8617dabfa4f..6176e6bce75 100644
--- a/odoo/tools/appdirs.py
+++ b/odoo/tools/appdirs.py
@@ -13,6 +13,7 @@ from __future__ import print_function
 #   http://support.microsoft.com/default.aspx?scid=kb;en-us;310294#XSLTH3194121123120121120120
 # - Mac OS X: http://developer.apple.com/documentation/MacOSX/Conceptual/BPFileSystem/index.html
 # - XDG spec for Un*x: http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html
+from . import pycompat
 
 __version_info__ = (1, 3, 0)
 __version__ = '.'.join(str(v) for v in __version_info__)
@@ -21,12 +22,6 @@ __version__ = '.'.join(str(v) for v in __version_info__)
 import sys
 import os
 
-PY3 = sys.version_info[0] == 3
-
-if PY3:
-    unicode = str
-
-
 
 def user_data_dir(appname=None, appauthor=None, version=None, roaming=False):
     r"""Return full path to the user-specific data dir for this application.
@@ -397,7 +392,7 @@ def _get_win_folder_with_pywin32(csidl_name):
     # not return unicode strings when there is unicode data in the
     # path.
     try:
-        dir = unicode(dir)
+        dir = pycompat.text_type(dir)
 
         # Downgrade to short path name if have highbit chars. See
         # <http://bugs.activestate.com/show_bug.cgi?id=85099>.
diff --git a/odoo/tools/cache.py b/odoo/tools/cache.py
index 2554331ce9b..1226038a21c 100644
--- a/odoo/tools/cache.py
+++ b/odoo/tools/cache.py
@@ -8,7 +8,7 @@ from decorator import decorator
 from inspect import formatargspec, getargspec
 import logging
 
-from odoo.tools import pycompat
+from . import pycompat
 
 unsafe_eval = eval
 
@@ -135,7 +135,7 @@ class ormcache_multi(ormcache):
     def determine_key(self):
         """ Determine the function that computes a cache key from arguments. """
         assert self.skiparg is None, "ormcache_multi() no longer supports skiparg"
-        assert isinstance(self.multi, basestring), "ormcache_multi() parameter multi must be an argument name"
+        assert isinstance(self.multi, pycompat.string_types), "ormcache_multi() parameter multi must be an argument name"
 
         super(ormcache_multi, self).determine_key()
 
diff --git a/odoo/tools/config.py b/odoo/tools/config.py
index 97c0d2f3d09..ee6c03a7e2e 100644
--- a/odoo/tools/config.py
+++ b/odoo/tools/config.py
@@ -5,15 +5,13 @@ try:
     import configparser as ConfigParser
 except ImportError:
     import ConfigParser
-    
+
+import logging
 import optparse
 import os
 import sys
 import odoo
-import odoo.conf
-import odoo.loglevels as loglevels
-import logging
-import odoo.release as release
+from .. import release, conf, loglevels
 from . import appdirs, pycompat
 
 
@@ -398,10 +396,10 @@ class configmanager(object):
             if getattr(opt, arg):
                 self.options[arg] = getattr(opt, arg)
             # ... or keep, but cast, the config file value.
-            elif isinstance(self.options[arg], basestring) and self.casts[arg].type in optparse.Option.TYPE_CHECKER:
+            elif isinstance(self.options[arg], pycompat.string_types) and self.casts[arg].type in optparse.Option.TYPE_CHECKER:
                 self.options[arg] = optparse.Option.TYPE_CHECKER[self.casts[arg].type](self.casts[arg], arg, self.options[arg])
 
-        if isinstance(self.options['log_handler'], basestring):
+        if isinstance(self.options['log_handler'], pycompat.string_types):
             self.options['log_handler'] = self.options['log_handler'].split(',')
         self.options['log_handler'].extend(opt.log_handler)
 
@@ -433,7 +431,7 @@ class configmanager(object):
             if getattr(opt, arg) is not None:
                 self.options[arg] = getattr(opt, arg)
             # ... or keep, but cast, the config file value.
-            elif isinstance(self.options[arg], basestring) and self.casts[arg].type in optparse.Option.TYPE_CHECKER:
+            elif isinstance(self.options[arg], pycompat.string_types) and self.casts[arg].type in optparse.Option.TYPE_CHECKER:
                 self.options[arg] = optparse.Option.TYPE_CHECKER[self.casts[arg].type](self.casts[arg], arg, self.options[arg])
 
         self.options['root_path'] = os.path.abspath(os.path.expanduser(os.path.expandvars(os.path.join(os.path.dirname(__file__), '..'))))
@@ -471,9 +469,9 @@ class configmanager(object):
         if opt.save:
             self.save()
 
-        odoo.conf.addons_paths = self.options['addons_path'].split(',')
+        conf.addons_paths = self.options['addons_path'].split(',')
 
-        odoo.conf.server_wide_modules = [
+        conf.server_wide_modules = [
             m.strip() for m in self.options['server_wide_modules'].split(',') if m.strip()
         ]
 
@@ -575,7 +573,7 @@ class configmanager(object):
 
     def __setitem__(self, key, value):
         self.options[key] = value
-        if key in self.options and isinstance(self.options[key], basestring) and \
+        if key in self.options and isinstance(self.options[key], pycompat.string_types) and \
                 key in self.casts and self.casts[key].type in optparse.Option.TYPE_CHECKER:
             self.options[key] = optparse.Option.TYPE_CHECKER[self.casts[key].type](self.casts[key], key, self.options[key])
 
diff --git a/odoo/tools/convert.py b/odoo/tools/convert.py
index 66e72c5d3ff..7da9f4e4412 100644
--- a/odoo/tools/convert.py
+++ b/odoo/tools/convert.py
@@ -16,7 +16,6 @@ import pytz
 from lxml import etree, builder
 
 import odoo
-import odoo.release
 from . import assertion_report, pycompat
 from .config import config
 from .misc import file_open, unquote, ustr, SKIPPED_ELEMENT_TYPES
@@ -683,7 +682,7 @@ form: module.record_id""" % (xml_id,)
                         f_val = int(f_val)
                     elif model._fields[f_name].type in ['float', 'monetary']:
                         f_val = float(f_val)
-                    elif model._fields[f_name].type == 'boolean' and isinstance(f_val, basestring):
+                    elif model._fields[f_name].type == 'boolean' and isinstance(f_val, pycompat.string_types):
                         f_val = str2bool(f_val)
             res[f_name] = f_val
 
@@ -893,7 +892,7 @@ def convert_xml_import(cr, module, xmlfile, idref=None, mode='init', noupdate=Fa
 
     if idref is None:
         idref={}
-    if isinstance(xmlfile, basestring):
+    if isinstance(xmlfile, pycompat.string_types):
         xml_filename = xmlfile
     else:
         xml_filename = xmlfile.name
diff --git a/odoo/tools/misc.py b/odoo/tools/misc.py
index 8d3854aeb6d..b348e983a2e 100644
--- a/odoo/tools/misc.py
+++ b/odoo/tools/misc.py
@@ -465,7 +465,7 @@ def human_size(sz):
     if not sz:
         return False
     units = ('bytes', 'Kb', 'Mb', 'Gb')
-    if isinstance(sz,basestring):
+    if isinstance(sz,pycompat.string_types):
         sz=len(sz)
     s, i = float(sz), 0
     while s >= 1024 and i < len(units)-1:
@@ -798,7 +798,7 @@ class mute_logger(object):
 
     def __enter__(self):
         for logger in self.loggers:
-            assert isinstance(logger, basestring),\
+            assert isinstance(logger, pycompat.string_types),\
                 "A logger name must be a string, got %s" % type(logger)
             logging.getLogger(logger).addFilter(self)
 
@@ -1073,7 +1073,7 @@ def formatLang(env, value, digits=None, grouping=True, monetary=False, dp=False,
                 if not digits and digits is not 0:
                     digits = DEFAULT_DIGITS
 
-    if isinstance(value, (str, unicode)) and not value:
+    if isinstance(value, pycompat.string_types) and not value:
         return ''
 
     lang = env.user.company_id.partner_id.lang or 'en_US'
@@ -1108,7 +1108,7 @@ def format_date(env, value, lang_code=False, date_format=False):
         return ''
     if isinstance(value, datetime.datetime):
         value = value.date()
-    elif isinstance(value, basestring):
+    elif isinstance(value, pycompat.string_types):
         if len(value) < DATE_LENGTH:
             return ''
         value = value[:DATE_LENGTH]
diff --git a/odoo/tools/pycompat.py b/odoo/tools/pycompat.py
index ff229f0562c..e4111668d24 100644
--- a/odoo/tools/pycompat.py
+++ b/odoo/tools/pycompat.py
@@ -10,6 +10,15 @@ if PY2:
     unichr = unichr
     text_type = unicode
     string_types = (str, unicode)
+    def to_native(source, encoding='utf-8', falsy_empty=False):
+        if not source and falsy_empty:
+            return ''
+
+        if isinstance(source, text_type):
+            return source.encode(encoding)
+
+        return str(source)
+
     integer_types = (int, long)
 
     keys = lambda d: iter(d.iterkeys())
@@ -19,6 +28,11 @@ if PY2:
     # noinspection PyUnresolvedReferences
     from itertools import imap, izip, ifilter
 
+    def implements_to_string(cls):
+        cls.__unicode__ = cls.__str__
+        cls.__str__ = lambda x: x.__unicode__().encode('utf-8')
+        return cls
+
     def implements_iterator(cls):
         cls.next = cls.__next__
         del cls.__next__
@@ -30,6 +44,15 @@ else:
     unichr = chr
     text_type = str
     string_types = (str,)
+    def to_native(source, encoding='utf-8', falsy_empty=False):
+        if not source and falsy_empty:
+            return ''
+
+        if isinstance(source, bytes):
+            return source.decode(encoding)
+
+        return str(source)
+
     integer_types = (int,)
 
     keys = lambda d: iter(d.keys())
@@ -40,6 +63,9 @@ else:
     izip = zip
     ifilter = filter
 
+    def implements_to_string(cls):
+        return cls
+
     def implements_iterator(cls):
         return cls
 
@@ -47,3 +73,20 @@ else:
         if value.__traceback__ != tb:
             raise value.with_traceback(tb)
         raise value
+
+def to_text(source):
+    """ Generates a text value (an instance of text_type) from an arbitrary 
+    source.
+    
+    * False and None are converted to empty strings
+    * text is passed through
+    * bytes are decoded as UTF-8
+    * rest is textified via the current version's relevant data model method
+    """
+    if source is None or source is False:
+        return u''
+
+    if isinstance(source, bytes):
+        return source.decode('utf-8')
+
+    return text_type(source)
diff --git a/odoo/tools/safe_eval.py b/odoo/tools/safe_eval.py
index de767fb7453..fec89fac087 100644
--- a/odoo/tools/safe_eval.py
+++ b/odoo/tools/safe_eval.py
@@ -26,6 +26,7 @@ import werkzeug
 
 from . import pycompat
 from .misc import ustr
+from . import pycompat
 
 import odoo
 
@@ -267,8 +268,9 @@ _BUILTINS = {
     'True': True,
     'False': False,
     'None': None,
+    'bytes': bytes,
     'str': str,
-    'unicode': unicode,
+    'unicode': pycompat.text_type,
     'bool': bool,
     'int': int,
     'float': float,
diff --git a/odoo/tools/test_reports.py b/odoo/tools/test_reports.py
index cad44431c1d..6a6401eb896 100644
--- a/odoo/tools/test_reports.py
+++ b/odoo/tools/test_reports.py
@@ -7,15 +7,14 @@
     through the code of yaml tests.
 """
 
-import odoo
-import odoo.tools as tools
 import logging
-
-from odoo.tools import pycompat
-from odoo.tools.safe_eval import safe_eval
-from subprocess import Popen, PIPE
 import os
 import tempfile
+from subprocess import Popen, PIPE
+
+from .. import api
+from . import pycompat, ustr, config
+from .safe_eval import safe_eval
 
 _logger = logging.getLogger(__name__)
 _test_logger = logging.getLogger('odoo.tests')
@@ -30,7 +29,7 @@ def try_report(cr, uid, rname, ids, data=None, context=None, our_module=None, re
         context = {}
     _test_logger.info("  - Trying %s.create(%r)", rname, ids)
 
-    env = odoo.api.Environment(cr, uid, context)
+    env = api.Environment(cr, uid, context)
 
     report_id = env['ir.actions.report'].search([('report_name', '=', rname)], limit=1)
     if not report_id:
@@ -41,12 +40,12 @@ def try_report(cr, uid, rname, ids, data=None, context=None, our_module=None, re
     if not res_data:
         raise ValueError("Report %s produced an empty result!" % rname)
 
-    if tools.config['test_report_directory']:
-        open(os.path.join(tools.config['test_report_directory'], rname+ '.'+res_format), 'wb+').write(res_data)
+    if config['test_report_directory']:
+        open(os.path.join(config['test_report_directory'], rname+ '.'+res_format), 'wb+').write(res_data)
 
     _logger.debug("Have a %s report for %s, will examine it", res_format, rname)
     if res_format == 'pdf':
-        if res_data[:5] != '%PDF-':
+        if res_data[:5] != b'%PDF-':
             raise ValueError("Report %s produced a non-pdf header, %r" % (rname, res_data[:10]))
         res_text = False
         try:
@@ -56,7 +55,7 @@ def try_report(cr, uid, rname, ids, data=None, context=None, our_module=None, re
 
             proc = Popen(['pdftotext', '-enc', 'UTF-8', '-nopgbrk', rfname, '-'], shell=False, stdout=PIPE)
             stdout, stderr = proc.communicate()
-            res_text = tools.ustr(stdout)
+            res_text = ustr(stdout)
             os.unlink(rfname)
         except Exception:
             _logger.debug("Unable to parse PDF report: install pdftotext to perform automated tests.")
@@ -92,14 +91,14 @@ def try_report_action(cr, uid, action_id, active_model=None, active_ids=None,
                 Eg. 'OK' or 'fa-print'
         :param our_module: the name of the calling module (string), like 'account'
     """
-    if not our_module and isinstance(action_id, basestring):
+    if not our_module and isinstance(action_id, pycompat.string_types):
         if '.' in action_id:
             our_module = action_id.split('.', 1)[0]
 
     context = dict(context or {})
     # TODO context fill-up
 
-    env = odoo.api.Environment(cr, uid, context)
+    env = api.Environment(cr, uid, context)
 
     def log_test(msg, *args):
         _test_logger.info("  - " + msg, *args)
@@ -113,7 +112,7 @@ def try_report_action(cr, uid, action_id, active_model=None, active_ids=None,
     if not wiz_buttons:
         wiz_buttons = []
 
-    if isinstance(action_id, basestring):
+    if isinstance(action_id, pycompat.string_types):
         if '.' in action_id:
             _, act_xmlid = action_id.split('.', 1)
         else:
@@ -138,7 +137,7 @@ def try_report_action(cr, uid, action_id, active_model=None, active_ids=None,
         if datas.get('id',False):
             context.update( {'active_id': datas.get('id',False), 'active_ids': datas.get('ids',[]), 'active_model': datas.get('model',False)})
         context1 = action.get('context', {})
-        if isinstance(context1, basestring):
+        if isinstance(context1, pycompat.string_types):
             context1 = safe_eval(context1, dict(context))
         context.update(context1)
         env = env(context=context)
diff --git a/odoo/tools/translate.py b/odoo/tools/translate.py
index 49aeb2864a8..dbf995a5161 100644
--- a/odoo/tools/translate.py
+++ b/odoo/tools/translate.py
@@ -127,9 +127,7 @@ class UNIX_LINE_TERMINATOR(csv.excel):
 csv.register_dialect("UNIX", UNIX_LINE_TERMINATOR)
 
 
-#
-# Helper functions for translating fields
-#
+# FIXME: holy shit this whole thing needs to be cleaned up hard it's a mess
 def encode(s):
     if isinstance(s, unicode):
         return s.encode('utf8')
@@ -280,18 +278,18 @@ def translate_xml_node(node, callback, parse, serialize):
 
 
 def parse_xml(text):
-    return etree.fromstring(encode(text))
+    return etree.fromstring(text)
 
 def serialize_xml(node):
-    return etree.tostring(node, method='xml', encoding='utf8').decode('utf8')
+    return etree.tostring(node, method='xml', encoding='unicode')
 
 _HTML_PARSER = etree.HTMLParser(encoding='utf8')
 
 def parse_html(text):
-    return html.fragment_fromstring(encode(text), parser=_HTML_PARSER)
+    return html.fragment_fromstring(text, parser=_HTML_PARSER)
 
 def serialize_html(node):
-    return etree.tostring(node, method='html', encoding='utf8').decode('utf8')
+    return etree.tostring(node, method='html', encoding='unicode')
 
 
 def xml_translate(callback, value):
@@ -307,7 +305,7 @@ def xml_translate(callback, value):
         return serialize_xml(result)
     except etree.ParseError:
         # fallback for translated terms: use an HTML parser and wrap the term
-        root = parse_html("<div>%s</div>" % value)
+        root = parse_html(u"<div>%s</div>" % value)
         result = translate_xml_node(root, callback, parse_xml, serialize_xml)
         # remove tags <div> and </div> from result
         return serialize_xml(result)[5:-6]
@@ -643,14 +641,13 @@ class PoFile(object):
             # only strings in python code are python formated
             self.buffer.write(u"#, python-format\n")
 
-        if not isinstance(trad, unicode):
-            trad = unicode(trad, 'utf8')
-        if not isinstance(source, unicode):
-            source = unicode(source, 'utf8')
-
-        msg = u"msgid %s\n"      \
-              u"msgstr %s\n\n"   \
-                  % (quote(source), quote(trad))
+        msg = (
+            u"msgid %s\n"
+            u"msgstr %s\n\n"
+        ) % (
+            quote(pycompat.text_type(source)), 
+            quote(pycompat.text_type(trad))
+        )
         self.buffer.write(msg)
 
 
@@ -1109,7 +1106,7 @@ def trans_load_data(cr, fileobj, fileformat, lang, lang_name=None, verbose=True,
                 return
 
             if isinstance(res_id, pycompat.integer_types) or \
-                    (isinstance(res_id, basestring) and res_id.isdigit()):
+                    (isinstance(res_id, pycompat.string_types) and res_id.isdigit()):
                 dic['res_id'] = int(res_id)
                 if module_name:
                     dic['module'] = module_name
diff --git a/odoo/tools/yaml_import.py b/odoo/tools/yaml_import.py
index 4cb2e7ea184..6cf4cc357eb 100644
--- a/odoo/tools/yaml_import.py
+++ b/odoo/tools/yaml_import.py
@@ -12,8 +12,7 @@ from lxml import etree
 import yaml
 
 import odoo
-from . import assertion_report
-from . import yaml_tag, pycompat
+from . import assertion_report, pycompat, yaml_tag
 from .config import config
 from .misc import file_open, DEFAULT_SERVER_DATE_FORMAT, DEFAULT_SERVER_DATETIME_FORMAT
 from odoo import SUPERUSER_ID
@@ -25,9 +24,6 @@ from .safe_eval import safe_eval
 
 _logger = logging.getLogger(__name__)
 
-def encode(s):
-    return s.encode('utf8') if isinstance(s, unicode) else s
-
 class YamlImportException(Exception):
     pass
 
@@ -41,7 +37,7 @@ def _is_yaml_mapping(node, tag_constructor):
     return value
 
 def is_comment(node):
-    return isinstance(node, basestring)
+    return isinstance(node, pycompat.string_types)
 
 def is_assert(node):
     return isinstance(node, yaml_tag.Assert) \
@@ -87,7 +83,7 @@ def is_ir_set(node):
     return _is_yaml_mapping(node, yaml_tag.IrSet)
 
 def is_string(node):
-    return isinstance(node, basestring)
+    return isinstance(node, pycompat.string_types)
 
 class RecordDictWrapper(dict):
     """
@@ -278,7 +274,7 @@ class YamlInterpreter(object):
         record, fields = next(pycompat.items(node))
         model = self.env[record.model]
         view_id = record.view
-        if view_id and (view_id is not True) and isinstance(view_id, basestring):
+        if view_id and (view_id is not True) and isinstance(view_id, pycompat.string_types):
             if '.' not in view_id:
                 view_id = self.module + '.' + view_id
             view_id = self.env.ref(view_id).id
@@ -358,7 +354,10 @@ class YamlInterpreter(object):
                         traverse(child, elems)
 
             elems = OrderedDict()
-            traverse(etree.fromstring(encode(view['arch'])), elems)
+            arch = view['arch']
+            if isinstance(arch, pycompat.text_type):
+                arch = arch.encode('utf-8')
+            traverse(etree.fromstring(arch), elems)
             return elems
 
         def is_readonly(field_elem):
@@ -584,7 +583,7 @@ class YamlInterpreter(object):
         assert python.model or python.id, "!python node must have attribute `model` or `id`"
         if python.id is None:
             record = self.env[python.model]
-        elif isinstance(python.id, basestring):
+        elif isinstance(python.id, pycompat.string_types):
             record = self.get_record(python.id)
         else:
             record = self.env[python.model].browse(python.id)