title: Update label of tkinter menubar item?
body: <p>Is it possible to change the label of an item in a menu with tkinter? </p>
  
  <p>In the following example, I'd like to change it from "An example item" (in the "File" menu) to a different value.</p>
  
  <pre class="lang-py prettyprint-override"><code>from tkinter import *
  
  root = Tk()
  menu_bar = Menu(root)
  
  file_menu = Menu(menu_bar, tearoff=False)
  file_menu.add_command(label="An example item", command=lambda: print('clicked!'))
  menu_bar.add_cascade(label="File", menu=file_menu)
  
  root.config(menu=menu_bar)
  root.mainloop()
  </code></pre>