We have changed our program from being an append-only form to an application capable of loading, viewing, and updating data from existing files. You learned how to make a read-write model, work with the ttk
Treeview, and modify the existing views and controller to read and update records.
In our next chapter, we'll be learning how to modify the look and feel of our application. We'll learn about using widget attributes, styles, and themes, as well as working with bitmapped graphics.