def deferred_to_columns_cb(self, target, model, fields):
        """
        Callback used by deferred_to_columns(). The "target" parameter should
        be a set instance.
        """
        table = model._meta.db_table
        if target not in table:
            target[table] = set()
        for field in fields:
            target[table].add(field.column)
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.5/django/db/models/sql/query.py/Query.deferred_to_columns_cb/swapped operands of `not in`