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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def for_user(self, user):
 """ All folders the given user can do something with. """

        qs = SharedMemberQuerySet(model=self.model, using=self._db, user=user)
        qs = qs.filter(Q(author=user) | Q(foldershareduser__user=user))
        return qs.distinct() & self.distinct()