from machine import Pin
import time

pin_nr_rot = 5
pin_nr_gelb = 9
pin_nr_gruen = 13

led_rot = Pin(pin_nr_rot, Pin.OUT)
led_gelb = Pin(pin_nr_gelb, Pin.OUT)
led_gruen = Pin(pin_nr_gruen, Pin.OUT)

while True:
  led_rot.toggle()
  time.sleep(0.5)
  led_gelb.toggle()
  time.sleep(0.5)
  led_gruen.toggle()
  time.sleep(0.5)