from machine import Pin
import time 

red= Pin(2,Pin.OUT)
green = Pin(4,Pin.OUT)
blue=Pin(16,Pin.OUT)

while True:
    red.value(1)
    green.value(0)
    blue.value(0)
    time.sleep(0.5)

    red.value(0)
    green.value(1)
    blue.value(0)
    time.sleep(0.5)

    red.value(1)
    green.value(1)
    blue.value(1)
    time.sleep(0.5)