Blink some LEDs

#https://roboticsbackend.com/raspberry-pi-control-led-python-3/
#https://lowvoltagelabs.com/products/pi-traffic/
#https://www.raspberrypi-spy.co.uk/2012/06/simple-guide-to-the-rpi-gpio-header-and-pins/
import RPi.GPIO as GPIO
import time
LED_G = 16 
LED_R = 20
LED_Y = 21 
GPIO.setmode(GPIO.BCM)
GPIO.setup(LED_R, GPIO.OUT)
GPIO.setup(LED_G, GPIO.OUT)
GPIO.setup(LED_Y, GPIO.OUT)
#
GPIO.output(LED_G, GPIO.HIGH)
time.sleep(1)
GPIO.output(LED_Y, GPIO.HIGH)
time.sleep(1)

GPIO.output(LED_R, GPIO.HIGH)

time.sleep(1)
GPIO.output(LED_R, GPIO.LOW)
time.sleep(1)

GPIO.output(LED_Y, GPIO.LOW)
time.sleep(1)

GPIO.output(LED_G, GPIO.LOW)

GPIO.cleanup()