import utime
start_time = utime.ticks_ms()

while True:
    current_time = utime.ticks_ms()
    elapsed_time = (current_time - start_time)//1000
    hours = int(elapsed_time // 3600)
    minutes = int((elapsed_time % 3600) // 60)
    seconds = int(elapsed_time % 60)
    time_tuple = utime.localtime(elapsed_time)
    time_str = "{:02d}:{:02d}:{:02d}".format(time_tuple[3], time_tuple[4], time_tuple[5])
    print(time_str)
    utime.sleep(1)