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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 pause_process(self, key):
 """Pause a specific processes."""

        if key in self.processes and key not in self.paused:
            os.killpg(os.getpgid(self.processes[key].pid), signal.SIGSTOP)
            self.queue[key]['status'] = 'paused'
            self.paused.append(key)
            return True
        return False