code: def list_containers(self, page_size=None):
          
          params = {}
  
          if page_size is not None:
              params['limit'] = page_size
  
          return pagination.Iterator(
              client=self._client,
              path='/mdb/{}/containers'.format(self._instance),
              params=params,
              response_class=mdb_pb2.ListContainersResponse,
              items_key='container',
              item_mapper=Container,
          )
docs: Lists the containers visible to this client.
  
          Containers are returned in lexicographical order.
  
          :rtype: :class:`.Container` iterator