If the shutdown timer is started, then show how much time you have with functional buttons.

from time import sleep

def timer(h, m, s):
    print("Shutdown Timer Started... ")
    counter = (h*3600) + (m*60) + s
    for i in range(counter):
        sleep(1)
        counter -= 1
        print(counter)

def show_timer(h, m, s):
    
    if (m > 59):
        print("Please enter a value less than 60 for minute")
    elif (s > 59):
        print("Please enter a value less than 60 for second")
    else:
        timer(h, m, s)

show_timer(0, 0, 1)