tkinter exit/quit/killing function threading out of mainloop

Question

I have this script that execute a long running function out of/before the main class/loop in tkinter and there is a button i created to quit the program completely using root.destroy() but it close the gui and the function keep running in the console or even as a background process after i created the executable file.

How to solve this issue?

snippets of my script:

 from tkinter import *
 import threading             

def download():
    #downloading a video file
def stop(): # stop button to close the gui and should terminate the download function too
   root.destroy()

class 
...
...
...
def downloadbutton():
    threading.Thread(target=download).start()

Answer 1

Make the thread a daemon to have it die when the main thread dies.

def downloadbutton():
    t = threading.Thread(target=download)
    t.daemon = True
    t.start()

For example:

import tkinter as tk
import threading
import time

def download():
    while True:
        time.sleep(1)
        print('tick tock')

def stop(): # stop button to close the gui and should terminate the download function too
   root.destroy()

def downloadbutton():
    t = threading.Thread(target=download)
    t.daemon = True
    t.start()

root = tk.Tk()
btn = tk.Button(text = "Start", command=downloadbutton)
btn.pack()
btn = tk.Button(text = "Stop", command=stop)
btn.pack()
root.mainloop()