如何使用画布悬停图像？TKinter

import tkinter as tk

def on_hover(event):
    canvas.itemconfig(image_item, image=hover_image)

def on_leave(event):
    canvas.itemconfig(image_item, image=normal_image)

root = tk.Tk()
canvas = tk.Canvas(root, width=400, height=400)
canvas.pack()

normal_image = tk.PhotoImage(file="normal_image.png")
hover_image = tk.PhotoImage(file="hover_image.png")

image_item = canvas.create_image(200, 200, image=normal_image)

canvas.tag_bind(image_item, "<Enter>", on_hover)
canvas.tag_bind(image_item, "<Leave>", on_leave)

root.mainloop()