There are several libraries that write GUI applications in Python. The most famous ones are Tkinter, wxPython, PyGTK, and PyQt. They all offer a wide range of tools and widgets that you can use to compose a GUI application.
The one I'm going to use for the rest of 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/3.7/library...
