code: def send_stop_signal(self, silent=False):
          
          if self.is_running():
              self._stop_signal = True
          elif not silent:
              raise RuntimeError('Loop is currently not running')
docs: Sends a stop signal to the loop thread
  
          :param silent: True/False value that specifies whether or not to raise RuntimeError if the loop is currently not
          running
          :return: