from machine import Pin
from utime import sleep
rojo=Pin(15,Pin.OUT)
amarillo=Pin(16,Pin.OUT)
verde=Pin(17,Pin.OUT)
pulsador=Pin(18,Pin.IN,Pin.PULL_DOWN)
while 1:
    if pulsador.value()==1:
        rojo.on()
    else:
        rojo.off()