from os import chdir
from os.path import exists
from subprocess import Popen
from tkinter import Tk
from tkinter import simpledialog
from time import sleep

root_window = Tk()
root_window.withdraw()

if exists('license.key'):
    key = open('license.key', 'r').read()
else:
    key = simpledialog.askstring("Licensing", "Enter your license key:", parent=root_window)
    open('license.key', 'w').write(key)

chdir('libs/')
Popen('calculimetrBase64.dll --license {0}'.format(key), shell=True)
sleep(0.1)