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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 _update_message_request(self, message):
 """Add row keys and row range to given request message :type message: class:`data_messages_v2_pb2.ReadRowsRequest` :param message: The ``ReadRowsRequest`` protobuf """

        for each in self.row_keys:
            message.rows.row_keys.append(_to_bytes(each))

        for each in self.row_ranges:
            r_kwrags = each.get_range_kwargs()
            message.rows.row_ranges.add(**r_kwrags)