WPE A3 covers object-oriented programming, for beginning Python developers. It'll cover:
- Defining classes and instances
- Defining methods
- Composition of objects
- Keeping track of shared state among instances
- Inheritance
- Basic "magic" methods, such as __str__ and __len__
- Class methods
There are beginner-level WPE courses, called A1, A2, and A3. A1 focuses on basic data structures, and A2 focuses on functions and modules.