def add_listener(self, listener):
        logger.debug('installing listener %r' % listener)
        if not isinstance(listener, SessionListener):
            raise SessionError("Listener must be a SessionListener type")
        with self._lock:
            self._listeners.add(listener)
Register a listener that will be notified of incoming messages and
dataset/ETHPy150Open ncclient/ncclient/ncclient/transport/session.py/Session.add_listener