Масштабирование изображения

from tkinter import *
from tkinter import messagebox
from PIL import ImageTk, Image
from tkinter import filedialog
from pynput.mouse import Listener
from pynput import mouse
import os
 
def about_click():
    messagebox.showinfo("Message", "Work with images.")
 
def openfn(): # Open a image
    filename = filedialog.askopenfilename(title='open')
    return filename
 
 
def open_img():
    x = openfn()
    img = Image.open(x)
    
    #img = img.resize((sizeH, sizeW)) #img = img.resize((sizeH, sizeW), Image.ANTIALIAS)
    img = ImageTk.PhotoImage(img)
    panel = Label(window, image=img)
    panel.image = img
    panel.pack()
    return img
 
def close_window (): # Window closing function
            if messagebox.askokcancel('Exit Application','Are you sure?'): 
                 window.destroy()
 
window = Tk()
window.title("The medicine")
 
window.resizable(width=True, height=True)
 
theimgage = open_img()
 
main_menu = Menu() #menu
file_menu = Menu() #submenu
file_menu.add_command(label="Open",command=open_img)
file_menu.add_separator()
file_menu.add_command(label="Exit",command=close_window)
 
main_menu.add_cascade(label="Menu", menu=file_menu)
main_menu.add_cascade(label="About",command=about_click)
window.config(menu=main_menu)
 
window.mainloop()

def open_img():
    x = openfn()
    img = Image.open(x)
 
    [l.destroy() for l in window.pack_slaves()]
        
    #img = img.resize((sizeH, sizeW)) #img = img.resize((sizeH, sizeW), Image.ANTIALIAS)
    img = ImageTk.PhotoImage(img)
    panel = Label(window, image=img)
    panel.image = img
    panel.pack()
    return img