diff --git a/addons/web/http.py b/addons/web/http.py
index 22b5522fa22..96b7275343d 100644
--- a/addons/web/http.py
+++ b/addons/web/http.py
@@ -471,18 +471,20 @@ from werkzeug.local import LocalStack
 
 _request_stack = LocalStack()
 
-def set_request(request):
-    class with_obj(object):
-        def __enter__(self):
-            _request_stack.push(request)
-        def __exit__(self, *args):
-            _request_stack.pop()
-    return with_obj()
 
+@contextlib.contextmanager
+def set_request(req):
+    _request_stack.push(req)
+    try:
+        yield
+    finally:
+        _request_stack.pop()
+
+
+request = _request_stack()
 """
     A global proxy that always redirect to the current request object.
 """
-request = _request_stack()
 
 #----------------------------------------------------------
 # Controller registration with a metaclass