tkinter loop

import Tkinter
import threading
import subprocess
import time
import win32gui
import win32con


def main_program():
    get_user_input()
    before = find_open_windows()
    launch_app_thread = threading.Thread(
        target=launch_software)
    launch_app_thread.start()
    button_thread = threading.Thread(
        target=InterruptButton)
    button_thread.start()
    wait_for_event()
    after = find_open_windows()
    close_recently_opened_windows(before, after)


def find_open_windows():
    list_of_open_windows = []
    win32gui.EnumWindows(
        lambda hwnd,
        resultList: resultList.append(hwnd),
        list_of_open_windows)
    return list_of_open_windows


def close_recently_opened_windows(before, after):
    for handle in after:
        if handle not in before:
            try:
                win32gui.PostMessage(handle, win32con.WM_CLOSE, 0, 0)
            except:
                pass
            time.sleep(.1)


def wait_for_event():
    print 'waiting for something important to happen'
    while not important_event:
        time.sleep(2)


class InterruptButton(threading.Thread):
    def __init__(self):
        threading.Thread.__init__(self)
        self.window = Tkinter.Tk()
        self.window.geometry('+0+0')
        self.window.overrideredirect(1)
        self.button = Tkinter.Button(
            self.window, text='Interrupt', command=self.interrupt)
        self.button.configure(background='red')
        self.button.pack()
        self.window.mainloop()

    def interrupt(self):
        print 'manually interrupted'
        global important_event
        important_event = True
        print 'now', important_event
        self.quit()

    def quit(self):
        self.window.quit()


def launch_software(test_program='notepad.exe', test_command='test.txt'):
    subprocess.Popen([test_program, test_command])


def get_user_input():
    popup = GetUserInput()
    if popup.command():
        return popup.command()


class GetUserInput:
    def __init__(self):
        self.master = Tkinter.Toplevel()
        self.label = Tkinter.Label(self.master)
        self.label.pack()
        self.entry = Tkinter.Entry(self.master)
        self.entry.pack()
        self.button = Tkinter.Button(
            self.master, text="OK", command=self.command,
            default=Tkinter.ACTIVE)
        self.button.pack()
        self.master.mainloop()

    def command(self, event=None):
        y = self.entry.get()
        self.master.withdraw()
        self.master.quit()
        return y


if __name__ == "__main__":
    root = Tkinter.Tk()
    root.withdraw()

    #important_event = False
    #main_program()

    while True:
        important_event = False
        main_program()