from machine import Pin
import utime

LEDS = [0,1,2,3]
L = [0,0,0,0]

for i in range(4):
    L[i]= Pin(LEDS[i],Pin.OUT)

while True:
    for i in range(4):
        L[i].value(1)
        utime.sleep(0.5)
        L[i].value(0)

def port_output(x):
    b= bin(x)
    b=b.replace("0b","")
    dif= 4-len(b)
    for i in range(0,dif):
        b= "0"+bin
    for i in range (0,4):
        if b[i]=="1":
            L[i].value(1)
        else:
            L[i].value(0) 
    return