Create a simple program in main.py:

import time
from cubloc import *
 
led_pin = 25
Output(led_pin)
 
while True:
    High(led_pin)
    print("LED ON")
    time.sleep(0.5)
 
    Low(led_pin)
    print("LED OFF")
    time.sleep(0.5)

This toggles the onboard LED every 500 ms.