GUI tkinter зависание интерфейса

import tkinter as Tk
import threading
import time
 
def task():
    while not kill_switch.is_set():
 
        print('ЗДЕСЬ КОД ПРОГРАММЫ')
 
        time.sleep(1)
 
def start_thread():
    global kill_switch, sub_thread
    kill_switch = threading.Event()
    sub_thread = threading.Thread(target=task)
    sub_thread.start()
 
def stop_thread():
    kill_switch.set()
    sub_thread.join()
 
root = Tk.Tk()
 
Tk.Button(root, text='START', command=start_thread, height=5, width=20,).pack(side=Tk.LEFT)
Tk.Button(root, text='STOP', command=stop_thread, height=5, width=20,).pack(side=Tk.LEFT)
Tk.Button(root, text='QUIT', command=root.quit, height=5, width=20,).pack(side=Tk.LEFT)
 
root.mainloop()

import tkinter as Tk
 
root = Tk.Tk()
run = False
 
def worker():
    print('ЗДЕСЬ КОД ПРОГРАММЫ')
    if run:
        root.after(500, worker)
 
def start_timer():
    global run
    run = True
    root.after(0, worker)
 
def stop_timer():
    global run
    if run:
        print('halting.')
        run = False
 
Tk.Button(root, text='START', command=start_timer,
        height=5, width=20,).pack(side=Tk.LEFT)
Tk.Button(root, text='STOP', command=stop_timer,
        height=5, width=20,).pack(side=Tk.LEFT)
Tk.Button(root, text='QUIT', command=root.quit,
        height=5, width=20,).pack(side=Tk.LEFT)
 
root.mainloop()

import tkinter as Tk
 
root = Tk.Tk()
root.title('Timer test')
root.geometry("200x100+200+200")
 
class TkJob:
 
    def __init__(self, arange, brange, interval, root):
        self.amin, self.amax = arange
        self.bmin, self.bmax = brange
        self.root = root
        self.interval = interval
        self.a, self.b = self.amin, self.bmin
        self.run = False
 
    def step(self):
 
        if not self.run:
            return
 
        print('ЗДЕСЬ КОД ПРОГРАММЫ')
 
        if self.run:
            self.root.after(self.interval, self.step)
 
    def start(self):
        print('job is running.')
        self.run = True
 
    def stop(self):
        print('job is halted.')
        self.run = False
 
def start_job():
    j.start()
    root.after(0, j.step)
 
def stop_job():
    if j.run:
        print('halting.')
        j.stop()
 
j = TkJob((0, 3), (0, 5), 500, root)
 
Tk.Button(root, text='START', command=start_job,
        height=5, width=20,).pack(side=Tk.LEFT)
Tk.Button(root, text='STOP', command=stop_job,
        height=5, width=20,).pack(side=Tk.LEFT)
Tk.Button(root, text='QUIT', command=root.quit,
        height=5, width=20,).pack(side=Tk.LEFT)
 
root.mainloop()

from tkinter import *
 
def work():
    print('working')
 
root = Tk()
 
start = Button(root, text='start', command=lambda: print('working'))
start.pack()
 
stop = Button(root, text='stop', command=lambda: exit())
stop.pack()
 
root.mainloop()