gpiozero example that could allow reboot and shutdown button on one key

held_button.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
# example gpiozero code that could be used to have a reboot
#  and a shutdown function on one GPIO button
# scruss - 2017-10

from gpiozero import Button
from signal import pause

held_for=0.0

def rls():
        global held_for
        print("released!")
        print("released after", held_for, "seconds.")
        # example code showing what to do with this time
        if (held_for > 5.0):
                print("I could shut down now …")
        elif (held_for > 2.0):
                print("I could reboot now …")
        else:
                print("I'm not going to do anything now …")
                held_for = 0.0

def hld():
        # callback for when button is held
        #  is called every hold_time seconds
        global held_for
        # need to use max() as held_time resets to zero on last callback
        held_for = max(held_for, button.held_time + button.hold_time)
        print("held for", held_for, "seconds.")

button=Button(4, hold_time=1.0, hold_repeat=True)
button.when_held = hld
button.when_released = rls

pause()