from machine import Pin
from time import sleep
led1= Pin(1,Pin.OUT);
led2= Pin(8,Pin.OUT);
led3 = Pin(2,Pin.OUT);
while True:
    led1.on()
    led2.off()
    led3.off()
    sleep(1)
    led2.off()
    led3.off()
    led1.on()
    sleep(1)
    led3.off()
    led1.on()
    led2.off()
    sleep(1)