def cancel(self):
        self.state = State.Done    
        if len(self.pilot_data) > 0: 
            CoordinationAdaptor.update_du(self)
Get count of devices for audio output, these devices are hardware oriented
dataset/ETHPy150Open saga-project/BigJob/pilot/impl/pilotdata_manager.py/DataUnit.cancel--crossover with--dataset/ETHPy150Open disqus/playa/playa/lib/vlc.py/libvlc_audio_output_device_count