In [14]:

    

# A BUTTON

import tkinter
from tkinter import messagebox
#import tkMessageBox

top = tkinter.Tk()
var = tkinter.StringVar()
label = tkinter.Message( top, textvariable=var)
var.set("Hey!? How are you doing?")

def helloCallBack():
    #messagebox.showinfo( "Hello Python", "Hello World")
    var.set("helloooooo")

B = tkinter.Button(top, text ="Hello", command = helloCallBack)

label.pack()
B.pack()
top.mainloop()


    

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