使用Tkinter的循环进度条？

import tkinter as tk
from tkinter import ttk

def start_progress():
    progress_bar.start()

def stop_progress():
    progress_bar.stop()

root = tk.Tk()

progress_bar = ttk.Progressbar(root, mode='indeterminate')
progress_bar.pack(pady=10)

start_button = tk.Button(root, text='Start', command=start_progress)
start_button.pack(pady=5)

stop_button = tk.Button(root, text='Stop', command=stop_progress)
stop_button.pack(pady=5)

root.mainloop()