from machine import ADC, Pin
import utime

Poten  = ADC(2)
led1 = Pin(18, Pin.OUT)
led2 = Pin(19, Pin.OUT)
led3 = Pin(20, Pin.OUT)
led4 = Pin(21, Pin.OUT)

a = [led1, led2, led3, led4]

while True:
    tiempo = 50 + int(Poten.read_u16()/327)
    for k in a:
        k.value(1)
        utime.sleep_ms(tiempo)
        k.value(0)
        utime.sleep_ms(tiempo)