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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) -> None: """ Stops a subprocess. Asks nicely. Waits. Asks less nicely. Repeat until subprocess is dead. .. todo:: cardinal_pythonlib.winservice.ProcessManager._kill: make it reliable under Windows """

        if not self.running:
            return
        try:
            self.wait(timeout_s=0)
            # If we get here: stopped already
        except subprocess.TimeoutExpired:  # still running
            for kill_level in self.ALL_KILL_LEVELS:
                tried_to_kill = self._terminate(level=kill_level)  # please stop
                if tried_to_kill:
                    try:
                        self.wait(timeout_s=self.kill_timeout_sec)
                        break
                    except subprocess.TimeoutExpired:  # failed to close
                        self.warning("Subprocess didn't stop when asked")
                        pass  # carry on escalating
        self.close_logs()
        self.running = False