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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 start(self, subthread=True):
 """Starts the loop Tries to start the loop. Raises RuntimeError if the loop is currently running. :param subthread: True/False value that specifies whether or not to start the loop within a subthread. If True the threading.Thread object is found in Loop._loop_thread. """

        if self.is_running():
            raise RuntimeError('Loop is currently running')
        else:
            self._lock.clear()
            self._stop_signal = False  # just in case
            self._in_subthread = subthread
            if subthread:
                self._loop_thread = threading.Thread(target=self._loop,
                                                     args=self.args,
                                                     kwargs=self.kwargs)
                self._loop_thread.start()
            else:
                self._loop(*self.args, **self.kwargs)