from machine import Pin
import time

# Define LEDs
red = Pin(15, Pin.OUT)
yellow = Pin(14, Pin.OUT)
green = Pin(13, Pin.OUT)

while True:
    # RED ON
    red.value(1)
    yellow.value(0)
    green.value(0)
    time.sleep(5)

    # GREEN ON
    red.value(0)
    yellow.value(0)
    green.value(1)
    time.sleep(5)

    # YELLOW ON
    red.value(0)
    yellow.value(1)
    green.value(0)
    time.sleep(2)