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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, timeout=15):
 """Stop the subprocess. Keyword Arguments **timeout** Time in seconds to wait for a process and its children to exit. """

        pp = self.pid
        if pp:
            try:
                kill_process_nicely(pp, timeout=timeout)
            except psutil.NoSuchProcess:
                pass