Rotation d'image sur tkinter

import tkinter as tk
from PIL import Image, ImageTk
import time

root = tk.Tk ()
canvas = tk.Canvas (root, width = img.size[0], height = img.size[1], bg = "white")
canvas.pack ()

def rotate (degré):
    global img
    img = img.rotate (degré)
    global tkimg
    tkimg = ImageTk.PhotoImage (img)
    canvas.create_image (img.size[0]/2,img.size[1]/2, image = tkimg, tags = "img")
    
img = Image.open ("target1.png")

rotate(0)

def pressed (event):
    rotate (90)
canvas.tag_bind ("img", "<B1-Motion>", pressed)
root.mainloop ()