from machine import Pin
from time import sleep
LED1 = Pin(6, Pin.OUT)
LED2 = Pin(7, Pin.OUT)
LED3 = Pin(8, Pin.OUT)
LED4 = Pin(9, Pin.OUT)
while True:
LED1.on()
LED2.on()
LED3.on()
LED4.on()
sleep(1)
LED1.off()
LED2.off()
LED3.off()
LED4.off()
sleep(1)