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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 unpack(cls, msg, client, server, request_id):
 """Parse message and return an `OpGetMore`. Takes the client message as bytes, the client and server socket objects, and the client 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)