new_contents: #!/usr/bin/env python3
  # -*- coding: utf-8 -*-
  
  # Copyright (c) 2016 Jérémie DECOCK (http://www.jdhp.org)
  
  # Permission is hereby granted, free of charge, to any person obtaining a copy
  # of this software and associated documentation files (the "Software"), to deal
  # in the Software without restriction, including without limitation the rights
  # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  # copies of the Software, and to permit persons to whom the Software is
  # furnished to do so, subject to the following conditions:
  
  # The above copyright notice and this permission notice shall be included in
  # all copies or substantial portions of the Software.
   
  # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  # THE SOFTWARE.
  
  # See also: http://effbot.org/tkinterbook/checkbutton.htm
  
  import tkinter as tk
  
  root = tk.Tk()
  
  test_var = tk.IntVar()
  test_var.set(2)    # Initialize
  
  def callback():
      print("var = ", test_var.get())
  
  # CREATE A TOPLEVEL MENU ######################################################
  
  menubar = tk.Menu(root)
  
  # CREATE A PULLDOWN MENU ######################################################
  #
  # tearoff:
  #  "tearoff=1" permet à l'utilisateur de détacher le sous menu dans une
  #  fenêtre à part.
  
  file_menu = tk.Menu(menubar, tearoff=0)
  file_menu.add_radiobutton(label="One",   variable=test_var, value=1, command=callback)
  file_menu.add_radiobutton(label="Two",   variable=test_var, value=2, command=callback)
  file_menu.add_radiobutton(label="Three", variable=test_var, value=3, command=callback)
  
  menubar.add_cascade(label="Test", menu=file_menu)
  
  # DISPLAY THE MENU ############################################################
  #
  # The config method is used to attach the menu to the root window. The
  # contents of that menu is used to create a menubar at the top of the root
  # window. There is no need to pack the menu, since it is automatically
  # displayed by Tkinter.
  
  root.config(menu=menubar)
  
  root.mainloop()
  
  
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