from machine import Pin
from time import sleep

red = Pin(8, Pin.OUT)
blue = Pin(11, Pin.OUT)
yellow = Pin(15, Pin.OUT)

while True:
    red.on()
    sleep(1.4)
    red.off()
    
    
    blue.on()
    sleep(1.4)
    blue.off()

    
    yellow.on()
    sleep(1.4)
    yellow.off()