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)
Sends a key press only, without releasing it.
dataset/ETHPy150Open ncclient/ncclient/ncclient/transport/session.py/Session.add_listener--crossover with--dataset/ETHPy150Open RoseOu/flasky/venv/lib/python2.7/site-packages/selenium/webdriver/common/action_chains.py/ActionChains.key_down