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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 time_window(self, window_width_ms):
 """Applies a system time window to the stream. Attributes: window_width_ms (int):
 The length of the window in ms. """

        op = Operator(
            _generate_uuid(),
            OpType.TimeWindow,
            "TimeWindow",
            num_instances=self.env.config.parallelism,
            other=window_width_ms)
        return self.__register(op)