reactions.py

import random
import time


def wait_random_time():
    r = random.random()
    time.sleep(r*10)


def turn_light_on():
    print('LIGHT')


def button_is_pressed():
    ready = input()
    return True


def main():

    times = []

    for i in range(5):

        wait_random_time()
        turn_light_on()
        start = time.time()

        if button_is_pressed():
            stop = time.time()
            elapsed = stop - start

            times.append(elapsed)
            print('That took {s} seconds'.format(s=elapsed))
            print('Get ready for the next one')
            print('3')
            time.sleep(1)
            print('2')
            time.sleep(1)
            print('1')
            time.sleep(1)


if __name__ == '__main__':

    print('Get Ready to test your reactions.')
    print('To play, just click the button when you see the green light come on.')
    print('')
    print('Enter any key when you are ready to start.')
    ready = input()

    main()