int ledPin1 = D2;
int ledPin2 = D3;

void setup() {
    pinMode(ledPin1, OUTPUT); // Use D2 as output pin
    digitalWrite(ledPin1, LOW);
    
    pinMode(ledPin2, OUTPUT); 
    digitalWrite(ledPin2, LOW);
}

void loop() {
    digitalWrite(ledPin1, HIGH);
    digitalWrite(ledPin2, LOW);
    delay(1000);
    digitalWrite(ledPin1, LOW);
    digitalWrite(ledPin2, HIGH);
    delay(1000);
}