Ticket #4050: base.py.diff

django/db/models/base.py

@@ -23 +23 @@
     def __new__(cls, name, bases, attrs):
         # If this isn't a subclass of Model, don't do anything special.
         try:
-            if not filter(lambda b: issubclass(b, Model), bases):
+            if not any(issubclass(base, Model) for base in bases):
                 return super(ModelBase, cls).__new__(cls, name, bases, attrs)
         except NameError:
             # 'Model' isn't defined yet, meaning we're looking at Django's own