carljm/django-model-utils — pull request #105 by patrys (2014-01-20 11:50:42+00:00)
Title: Don't try to access __slots__ during copy()

When subclassing Django will copy managers from the ancestor class. Copying in turn calls `copy.copy()` which checks whether the object uses `__slots__` or `__dict__`. This could result in the manager calling `self.get_queryset()` before all models get registered with the ORM.