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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 stop(self):
 """Stop the thread, making this object unusable."""

        if not self._dead:
            self._killed = True
            self._cancelled.set()
            self._busy_sem.release()
            self.join()
            if not self._ready_sem.acquire(False):
                warning("ISOTP Timer thread may not have stopped "
                        "correctly")