Structuring our application directory

Just as logically breaking our program into separate concerns helps us manage the logical complexity of each component, physically breaking the code into multiple files helps us keep the complexity of each file manageable. It also reinforces more isolation between components; for example, you can't share global variables, and if your models file imports tkinter, you know you're doing something wrong.

Basic directory structure

There is no official standard for laying out a Python application directory, but there are some common conventions that will help us keep things tidy and make it easier to package our software later on. Let's set up our directory structure as follows...