from machine import Pin 
import time

# Define LED pins
red_led = Pin(2, Pin.OUT)
yellow_led = Pin(3, Pin.OUT)
green_led = Pin(4, Pin.OUT)

while True:
    # Red light
    red_led.value(1)
    yellow_led.value(0)
    green_led.value(0)
    time.sleep(5)
    
    # Green light
    red_led.value(0)
    yellow_led.value(1)
    green_led.value(0)
    time.sleep(5)
    
    # Yellow light
    red_led.value(0)
    yellow_led.value(0)
    green_led.value(1)
    time.sleep(2)