@jmagsumbol Should the function be simply called start()? Does python_start() ever get called?
Alternatively, with a slight modification of MMM-PIR-Sensor, I think this could all be done within Node.js. You’d just need to examine how to handle the GPIO of the ultrasonic sensor in however it differs from a PIR sensor.
For actually turning the screen off and on, check out @cruunnerr‘s guide: https://forum.magicmirror.builders/topic/6291/howto-turn-on-off-your-monitor-time-based-pir-button-app/7