id,summary,reporter,owner,description,type,status,component,version,severity,resolution,keywords,cc,stage,has_patch,needs_docs,needs_tests,needs_better_patch,easy,ui_ux 20993,"filtering with F(), then count()ing throws a pickle ValueError",Artscoop ,nobody,"This {{{ results = self.only('id').filter(user=user, topic__isnull=False, date__gte=F('topic__updated')) }}} works, but {{{ total = self.only('id').filter(user=user, topic__isnull=False, date__gte=F('topic__updated')).count() }}} does not, and fails with a **ValueError : ctypes objects containing pointers cannot be pickled**. `aggregate()`, `values_list()` and `annotate()` also fail with the same error. `date` and `topic__updated` are `DateTimeField`s.",Uncategorized,closed,"Database layer (models, ORM)",1.5,Normal,duplicate,,,Unreviewed,0,0,0,0,0,0