def __init__(self, tty_device='/dev/ttyACM0'):
    self._serial = serial.Serial(tty_device, timeout=0.2)
    self._lock = threading.Lock()
def __init__(self, tty_device='/dev/ttyACM0'):
    self._serial = serial.Serial(tty_device, timeout=0.2)
    self._lock = threading.Lock()