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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_isupport_wallchops(self, value):
 """ Support for messaging every opped member or higher on a channel. Replaced by STATUSMSG. """

        for prefix, mode in self._nickname_prefixes.items():
            if mode == 'o':
                break
        else:
            prefix = '@'
        self._status_message_prefixes.add(prefix)