diff --git a/addons/purchase_manual/wizard/wizard_purchase_line_invoice.py b/addons/purchase_manual/wizard/wizard_purchase_line_invoice.py
index 89d7d188287..c65cefd97d0 100644
--- a/addons/purchase_manual/wizard/wizard_purchase_line_invoice.py
+++ b/addons/purchase_manual/wizard/wizard_purchase_line_invoice.py
@@ -24,6 +24,7 @@ import wizard
 import netsvc
 import ir
 import pooler
+import osv
 
 invoice_form = """<?xml version="1.0"?>
 <form string="Control invoices">