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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):
 """Hard stop the server and sub process"""

        self._end.value = True
        if self.background_process:
            try:
                self.background_process.terminate()
            except Exception:
                pass
        for task_id, values in self.current_tasks.items():
            try:
                values['proc'].terminate()
            except Exception:
                pass