code: def unpack(cls, msg, client, server, request_id):
          
          flags, = _UNPACK_INT(msg[:4])
          namespace, pos = _get_c_string(msg, 4)
          num_to_return, = _UNPACK_INT(msg[pos:pos + 4])
          pos += 4
          cursor_id, = _UNPACK_LONG(msg[pos:pos + 8])
          return OpGetMore(namespace=namespace, flags=flags, _client=client,
                           num_to_return=num_to_return, cursor_id=cursor_id,
                           request_id=request_id, _server=server)
docs: Parse message and return an `OpGetMore`.
  
          Takes the client message as bytes, the client and server socket objects,
          and the client request id.