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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_join(self, message):
 """ JOIN command. """

        nick, metadata = self._parse_user(message.source)
        self._sync_user(nick, metadata)

        channels = message.params[0].split(',')
        if self.is_same_nick(self.nickname, nick):
            # Add to our channel list, we joined here.
            for channel in channels:
                if not self.in_channel(channel):
                    self._create_channel(channel)

                # Request channel mode from IRCd.
                await self.rawmsg('MODE', channel)
        else:
            # Add user to channel user list.
            for channel in channels:
                if self.in_channel(channel):
                    self.channels[channel]['users'].add(nick)

        for channel in channels:
            await self.on_join(channel, nick)