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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:
 def mark_streamer(self, index):
 """Manually mark a streamer that should trigger. The next time check_streamers is called, the given streamer will be manually marked that it should trigger, which will cause it to trigger unless it has no data. Args: index (int):
 The index of the streamer that we should mark as manually triggered. Raises: ArgumentError: If the streamer index is invalid. """


        self._logger.debug("Marking streamer %d manually", index)
        if index >= len(self.streamers):
            raise ArgumentError("Invalid streamer index", index=index, num_streamers=len(self.streamers))

        self._manually_triggered_streamers.add(index)