//int light = D2;
//int buzzer = D4;
int light = 2;
int buzzer = 4;
void setup()  {
  pinMode(buzzer, OUTPUT);
  pinMode(light, OUTPUT);
}

void loop() {
  tone(buzzer, 500);
  digitalWrite(light, HIGH);
  delay(250);
  digitalWrite(light, LOW);
  noTone(buzzer);
  delay(250);
}