code: def is_sub_to_all(self, *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
docs: Given a list of super entities, return the entities that have those as a subset of their super entities.