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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_333(self, message):
 """ Topic setter and time on channel join. """

        target, channel, setter, timestamp = message.params
        if not self.in_channel(channel):
            return

        # No need to sync user since this is most likely outdated info.
        self.channels[channel]['topic_by'] = self._parse_user(setter)[0]
        self.channels[channel]['topic_set'] = datetime.datetime.fromtimestamp(int(timestamp))