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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_once(self):
 """ Execute the worker once. This method will return after a file change is detected. """

        self._capture_signals()
        self._start_monitor()
        try:
            self._run_worker()
        except KeyboardInterrupt:
            return
        finally:
            self._stop_monitor()
            self._restore_signals()