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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):
 """ SEND STOP SIGNAL, DO NOT BLOCK """

        with self.child_lock:
            children = copy(self.children)
        for c in children:
            DEBUG and c.name and Log.note("Stopping thread {{name|quote}}", name=c.name)
            c.stop()
        self.please_stop.go()

        DEBUG and Log.note("Thread {{name|quote}} got request to stop", name=self.name)