pyOnionGpio was written as a quick and dirty wrapper for the sysfs gpio interface. I wouldn't recommend using it for anything other than a hello world.

There are other (likely better) sysfs gpio libraries available for Python3:

https://pypi.org/project/gpio/ https://python-periphery.readthedocs.io/en/latest/gpio.html https://github.com/vitiral/gpio

Let us know how it goes!