USB Key/Lock v2

# USB Key/Lock
# Author: ILikeTurtles
# Description: Poll USB devices every 1.5 seconds. If 'KEY' is missing, lock Windows.
import win32com.client, time, ctypes

wmi = win32com.client.GetObject ("winmgmts:")
current_state = 'unknown'

# Functions
def check_key():
    "Checks if 'key' is present"
    KEY = "1504171129470875179607"
    LOCK = False
    for usb in wmi.InstancesOf ("Win32_USBHub"):
        usbdid = usb.DeviceID
        if usbdid.find(KEY) != -1:
            LOCK = True
    if LOCK:
        return "unlocked";
    else:
        return "locked";

print("USB Lock by Aaron Henderson")
print("System will lock without proper USB device.")

while True:
    new_state = check_key()
    if (new_state == 'locked') and (current_state == 'unlocked'):
        ctypes.windll.user32.LockWorkStation()
    else:
        current_state = new_state
    time.sleep(1.5)