import time
time.sleep(0.1)
from machine import Pin
led_pins = [Pin(0,Pin.OUT),Pin(1,Pin.OUT), Pin(2, Pin.OUT), Pin(3, Pin.OUT)]
repeticiones = 10
for _ in range(repeticiones):
    for i in range(4): 
        led_pins[i].on()
        time.sleep(1)
        if i > 0:
            led_pins[i-1].off()
        led_pins[3].off()