def ctcpPing(self, irc, msg, match):
        "^\x01PING(?: (.+))?\x01$"
        self.log.info('Received CTCP PING from %s', msg.prefix)
        payload = match.group(1)
        if payload:
            self._reply(irc, msg, match.group(1) % 'PING %s')
        else:
            self._reply(irc, msg, 'PING')
dataset/ETHPy150Open ProgVal/Limnoria/plugins/Ctcp/plugin.py/Ctcp.ctcpPing/swapped operands of `%`