Now, let's complete the code for the About and Help menus. The functionality is simple. When a user clicks on the Help or About menu, a message window pops up and waits for the user to respond by clicking on a button. Though we can easily code new Toplevel windows to show the About and Help messages, we will instead use a module called messagebox to achieve this functionality.
The messagebox module provides ready-made message boxes to display a wide variety of messages in applications. The functions available through this module include showinfo, showwarning, showerror, askquestion, askokcancel, askyesno, askyesnocancel, and askretrycancel, as shown in the following screenshot:
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To use this module, we simply import it into the current namespace by using the following command:
import tkinter.messagebox
A demonstration of the commonly used functions...