from machine import Pin, PWM
from time import sleep

# pin configuration
led_red = Pin(18, Pin.OUT)
led_yellow = Pin(19, Pin.OUT)
led_green = Pin(20, Pin.OUT)


def BuzzerFunc():
  buzzer = PWM(Pin(15))
  buzzer.freq(500)
  buzzer.duty_u16(1000)
  sleep(1)
  buzzer.duty_u16(0)


def ledBlink(led):
  led.on()
  sleep(0.5)
  led.off()
  sleep(0.5)


while True:
  ledBlink(led_red)
  ledBlink(led_yellow)
  ledBlink(led_green)

  ledBlink(led_yellow)
  BuzzerFunc()