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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 _register(self):
 """ Hijack registration to send a CAP LS first. """

        if self.registered:
            self.logger.debug("skipping cap registration, already registered!")
            return

        # Ask server to list capabilities.
        await self.rawmsg('CAP', 'LS', '302')

        # Register as usual.
        await super()._register()