code: def put_multi(self, entities):
          
          if isinstance(entities, Entity):
              raise ValueError("Pass a sequence of entities")
  
          if not entities:
              return
  
          current = self.current_batch
          in_batch = current is not None
  
          if not in_batch:
              current = self.batch()
              current.begin()
  
          for entity in entities:
              current.put(entity)
  
          if not in_batch:
              current.commit()
docs: Save entities in the Cloud Datastore.
  
          :type entities: list of :class:`google.cloud.datastore.entity.Entity`
          :param entities: The entities to be saved to the datastore.
  
          :raises: :class:`ValueError` if ``entities`` is a single entity.