ch2listing4.py

from gpiozero import TrafficHat
from time import sleep

th = TrafficHat()

try:
    while True:
        # Traffic light code
        # First, turn the green LED on
        th.lights.green.on()
        print(“Press the button to stop the lights!”)
        # Next, we want to wait until the button is pressed
        while(th.button.is_pressed == False):
            #While not pressed do nothing
            pass
        # Button has been pressed!
        th.lights.green.off()
        # Amber on for a couple of seconds
        th.lights.amber.on()
        sleep(2)
        th.lights.amber.off()
        # Turn the red on
        th.lights.red.on()
        # Buzz the buzzer 20 times with 0.1 second intervals
        th.buzzer.blink(0.1,0.1,20,False)
        sleep(1)
        th.lights.red.off()
        # Red off and blink amber 4 times with 0.5 second intervals
        th.lights.amber.blink(0.5,0.5,4,False)

except KeyboardInterrupt:
    exit()