Yes-No-box

import tkinter as tk
from tkinter import messagebox

root= tk.Tk()

canvas1 = tk.Canvas(root, width = 300, height = 300)
canvas1.pack()

def ExitApplication():
    MsgBox = tk.messagebox.askquestion ('Exit Application','Are you sure you want to exit the application',icon = 'warning')
    if MsgBox == 'yes':
       root.destroy()
    else:
        tk.messagebox.showinfo('Return','You will now return to the application screen')

button1 = tk.Button (root, text='Exit Application',command=ExitApplication,bg='brown',fg='white')
canvas1.create_window(150, 150, window=button1)

root.mainloop()