Second approach: a GUI application

There are several libraries for writing GUI applications in Python. Some of the most famous ones are Tkinter, wxPython, Kivy, and PyQt. They all offer a wide range of tools and widgets that you can use to compose a GUI application.

The one we are going to use in this chapter is Tkinter. Tkinter stands for Tk interface and it is the standard Python interface to the Tk GUI toolkit. Both Tk and Tkinter are available on most Unix platforms, macOS X, as well as on Windows systems.

Let's make sure that tkinter is installed properly on your system by running this command:

$ python -m tkinter

It should open a dialog window, demonstrating a simple Tk interface. If you can see that, we're good to go. However, if it doesn't work, please search for tkinter in the Python official documentation (https://docs.python.org/3.9/library/tkinter.html). You will find several links to resources that will help you get up and running with...