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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:
 async def on_raw_319(self, message):
 """ WHOIS active channels. """

        target, nickname, channels = message.params[:3]
        channels = {channel.lstrip() for channel in channels.strip().split(' ')}
        info = {
            'channels': channels
        }

        if nickname in self._pending['whois']:
            self._whois_info[nickname].update(info)