from machine import Pin
import time

# set up pin 15 as output device
LED = Pin(15, Pin.OUT)

while 1 + 1 == 2:

    LED.value(1)   # Turn LED on 
    time.sleep(1) # Wait for 1 second
    LED.value(0)  # Turn LED off
    time.sleep(1) # Wait for 1 second