'Called when the Connection is in a state that it can close after
a close has been requested. This happens, for example, when all of the
channels are closed that were open when the close request was made.'

def _on_close_ready(self):

    if self.is_closed:
        LOGGER.warning('_on_close_ready    invoked    when    already    closed')
        return
    self._send_connection_close(self.closing[0], self.closing[1])
