Tear down this object, after we've agreed to close with the server.

def _do_close(self):
        """
        Tear down this object, after we've agreed to close with the server.

        """
        AMQP_LOGGER.debug('Closed channel #%d' % self.channel_id)
        self.is_open = False
        del self.connection.channels[self.channel_id]
        self.channel_id = self.connection = None
        self.callbacks = {}