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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 run(self, once=False):
 """Runs the reactor in the main thread."""

        self._once = once
        self.start()
        while self.running:
            try:
                time.sleep(1.0)
            except KeyboardInterrupt:
                self.stop()
                self.join()