from machine import Pin
import time

Leds = [Pin(5,Pin.OUT),Pin(4,Pin.OUT),Pin(17,Pin.OUT)]
p_button=Pin(13,Pin.IN)

def cycle(Leds):
    for Led in range(len(Leds)):
        if Led == 0:
            Leds[Led].value(1)
            time.sleep_ms(500)
        else:
            Leds[Led-1].value(0)
            Leds[Led].value(1)
            time.sleep_ms(500)
    Leds[0].value(0)
    Leds[1].value(0)
    Leds[2].value(0)

while True:
  press=p_button.value()
  if press == True:
    cycle(Leds)