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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 bulk_add_entities(self, entities_and_kinds):
 """ Add many entities and sub-entity groups to this EntityGroup. :type entities_and_kinds: List of (Entity, EntityKind) pairs. :param entities_and_kinds: A list of entity, entity-kind pairs to add to the group. In the pairs the entity-kind can be ``None``, to add a single entity, or some entity kind to add all sub-entities of that kind. """

        memberships = [EntityGroupMembership(
            entity_group=self,
            entity=entity,
            sub_entity_kind=sub_entity_kind,
        ) for entity, sub_entity_kind in entities_and_kinds]
        created = EntityGroupMembership.objects.bulk_create(memberships)
        return created