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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 is_sub_to_all(self, *super_entities):
 """ Given a list of super entities, return the entities that have those as a subset of their super entities. """

        if super_entities:
            if len(super_entities) == 1:
                # Optimize for the case of just one super entity since this is a much less intensive query
                has_subset = EntityRelationship.objects.filter(
                    super_entity=super_entities[0]).values_list('sub_entity', flat=True)
            else:
                # Get a list of entities that have super entities with all types
                has_subset = EntityRelationship.objects.filter(
                    super_entity__in=super_entities).values('sub_entity').annotate(Count('super_entity')).filter(
                    super_entity__count=len(set(super_entities))).values_list('sub_entity', flat=True)

            return self.filter(id__in=has_subset)
        else:
            return self