code: def bulk_overwrite(self, entities_and_kinds):
          
          EntityGroupMembership.objects.filter(entity_group=self).delete()
          return self.bulk_add_entities(entities_and_kinds)
docs: Update the group to the given entities and sub-entity groups.
  
          After this operation, the only members of this EntityGroup
          will be the given entities, and sub-entity groups.
  
          :type entities_and_kinds: List of (Entity, EntityKind) pairs.
          :param entities_and_kinds: A list of entity, entity-kind pairs
              to set to the EntityGroup. 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.