如何让tkinter在函数内部运行？

import tkinter as tk

def run_tkinter():
    def on_button_click():
        label.config(text="Button clicked!")

    # 创建主窗口
    window = tk.Tk()

    # 创建标签
    label = tk.Label(window, text="Hello, tkinter!")
    label.pack()

    # 创建按钮
    button = tk.Button(window, text="Click me", command=on_button_click)
    button.pack()

    # 运行主循环
    window.mainloop()

# 调用函数运行tkinter
run_tkinter()