use `board.D13` on line 35
@@ -32,7 +32,7 @@ for pin in ledpins:
led.direction = digitalio.Direction.OUTPUT
leds.append(led)
-led = digitalio.DigitalInOut(D13)
+led = digitalio.DigitalInOut(board.D13)
led.switch_to_output()
print("Waiting for button presses")
