onclick butotn in python code example

Example 1: python button tkinter

from tkinter import *

wow = Tk()

def ree(hi):
  print(hi)
  
w = Button ( master=wow, command=ree('hi'), text="hi" )

Output:
  Tkinter:
    ______
   [  hi  ] <--- Button
    ------
  
  Shell:
    hi <--- on button pressed

Example 2: button tkinter

import Tkinter
import tkMessageBox

top = Tkinter.Tk()

def helloCallBack():
   tkMessageBox.showinfo( "Hello Python", "Hello World")

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

B.pack()
top.mainloop()