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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 execute(self, transition):
 """ Queue a transition for execution. :param transition: The transition """

        self._transitions.append(transition)
        if self._thread is None or not self._thread.isAlive():
            self._thread = threading.Thread(target=self._transition_loop)
            self._thread.setDaemon(True)
            self._thread.start()