from machine import Pin
import time

LED_RED_1 = Pin(2, Pin. OUT)
LED_YELLOW_1 = Pin(3, Pin.OUT)
LED_GREEN_1 = Pin(4, Pin.OUT)

LED_RED_2 = Pin(8, Pin.OUT)
LED_YELLOW_2 = Pin(9, Pin.OUT)
LED_GREEN_2 = Pin(10, Pin.OUT)

def init_pins():
    LED_RED_1.value(0)
    LED_YELLOW_1.value(0)
    LED_GREEN_1.value(0)
    
    LED_RED_2.value(0)
    LED_YELLOW_2.value(0)
    LED_GREEN_2.value(0)

def traffic_light_sequence():
    while True:
          #Turn on the LEDs and turn off the yellow and green LEDs for both trafic lights 
         LED_RED_1.value(1)
         LED_YELLOW_1.value(0)
         LED_GREEN_1.value(0)
        
         LED_RED_2.value(1)
         LED_YELLOW_2.value(0)
         LED_GREEN_2.value(0)
         time.sleep(3)
        
         #First traffic light :Red -> Green -> Yellow ->Red
         LED_RED_1.value(0)
         LED_GREEN_1.value(1)
         time.sleep(3) 

         LED_GREEN_1.value(0)
         LED_YELLOW_1.value(1)
         time.sleep(1)

         LED_YELLOW_1.value(0)
         LED_RED_1.value(1)
         time.sleep(1)

         # Second traffic light: Red - > Green - > Yellow - > Red
         LED_RED_2.value(0)
         LED_GREEN_2.value(1)
         time.sleep(3)

         LED_GREEN_2.value(0)
         LED_YELLOW_2.value(1)
         time.sleep(1)

         LED_YELLOW_2.value(0)
         LED_RED_2.value(1)
         time.sleep(1)

def main():
    init_pins()
    traffic_light_sequence()

if __name__== "__main__":
   main()