如何在tkiner中点击按钮后在画布上进行文本更新

import tkinter as tk

window = tk.Tk()

canvas = tk.Canvas(window, width=400, height=300)
canvas.pack()

text_var = tk.StringVar()
text_var.set("初始文本")

text = canvas.create_text(200, 150, text=text_var.get(), font=("Arial", 12), fill="black")

def update_text():
    new_text = "更新后的文本"
    text_var.set(new_text)
    canvas.itemconfigure(text, text=new_text)

button = tk.Button(window, text="点击更新文本", command=update_text)
button.pack()

window.mainloop()