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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 mark_broken(self, *, comment: str = None):
 """Mark broken. :param comment: Reason machine is broken. :type comment: `str` """

        params = {
            "system_id": self.system_id
        }
        if comment:
            params["comment"] = comment
        self._data = await self._handler.mark_broken(**params)
        return self