如何在tkinter python中再次调用函数时销毁预览标签

import tkinter as tk

def create_preview_label():
    # 创建预览标签
    preview_label = tk.Label(root, text="预览标签")
    preview_label.pack()

def call_function():
    # 检查预览标签是否存在
    if 'preview_label' in globals():
        # 销毁预览标签
        preview_label.destroy()
    
    # 再次调用函数创建预览标签
    create_preview_label()

root = tk.Tk()

# 创建按钮来调用函数
button = tk.Button(root, text="调用函数", command=call_function)
button.pack()

root.mainloop()