Return a new request message instance - extracts required data from connection object
        :param connection: connection object
        :param segments: a single segment instance, or a list/tuple of segment instances
        :returns: RequestMessage instance

def new(cls, connection, segments=()):
        """Return a new request message instance - extracts required data from connection object
        :param connection: connection object
        :param segments: a single segment instance, or a list/tuple of segment instances
        :returns: RequestMessage instance
        """
        return cls(connection.session_id, connection.get_next_packet_count(), segments,
                   autocommit=connection.autocommit)