int Nawa_Light = 15;
int Nawa_Light2 = 5;

  void setup () {
    pinMode(Nawa_Light, OUTPUT);
    pinMode(Nawa_Light2, OUTPUT);
  }

void loop() {
 digitalWrite(Nawa_Light, HIGH);
 digitalWrite(Nawa_Light2, LOW);
  delay(500);

  digitalWrite(Nawa_Light, LOW);
  digitalWrite(Nawa_Light2, HIGH);
    delay(500);
}