Sends a message to this connection.

        :param message: (Message), message to be sent to this connection.

def send_message(self, message):
        """
        Sends a message to this connection.

        :param message: (Message), message to be sent to this connection.
        """
        if not self.live():
            raise IOError("Connection is not live.")

        message.add_flag(BEGIN_END_FLAG)
        self.write(message.buffer)