At the moment, we don’t have any example for button debounce.
However, I’ve found some solutions (I haven’t tested them):
Pushbutton library for the pyboard – can be useful to get some ideas from it: https://github.com/peterhinch/Micropython-scheduler/blob/master/pushbutton.py
As well as this example: https://docs.micropython.org/en/v1.6/pyboard/pyboard/tutorial/debounce.html
I hope this helps.