def add_done_callback(self, fn):
        with self._condition:
            if self._state not in [CANCELLED, CANCELLED_AND_NOTIFIED, FINISHED]:
                self._done_callbacks.append(fn)
                return
        fn(self)
Set terminal status line: Data Terminal Ready
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/concurrent/concurrent/futures/_base.py/Future.add_done_callback--crossover with--dataset/ETHPy150Open Robot-Will/Stino/stino/pyarduino/base/pyserial/serialwin32.py/Win32Serial.setDTR