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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _on_open(self, _):
 """Joins the hack.chat channel and starts pinging."""

        nick = self._format_nick(self._nick, self._pwd)
        data = {"cmd": "join", "channel": self._channel, "nick": nick}
        self._send_packet(data)
        self._thread = True
        threading.Thread(target=self._ping).start()