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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_away(self, message):
 """ Process AWAY messages. """

        if 'away-notify' not in self._capabilities or not self._capabilities['away-notify']:
            return

        nick, metadata = self._parse_user(message.source)
        if nick not in self.users:
            return

        self._sync_user(nick, metadata)
        self.users[nick]['away'] = len(message.params) > 0
        self.users[nick]['away_message'] = message.params[0] if len(message.params) > 0 else None