diff --git a/src/authentic2_pratic/views.py b/src/authentic2_pratic/views.py
index 77e222a..adc5f7b 100644
--- a/src/authentic2_pratic/views.py
+++ b/src/authentic2_pratic/views.py
@@ -422,7 +422,7 @@ def return_json(request, data):
 
 def flatten(o):
     if isinstance(o, dict):
-        return {k: flatten(v) for k, v in o.iteritems()}
+        return dict((k, flatten(v)) for k, v in o.iteritems())
     elif isinstance(o, (tuple, list, set)):
         return o.__class__(flatten(v) for v in o)
     elif isinstance(o, (bool, unicode, int, long)):