Extending models

Extending a model is a way to write a set of fields and methods that can be shared in many different classes. This is also known as inheritance, which is a fundamental principle of the Python language, letting us write code once and reuse it over and over again. It is also a way to reuse or modify a class provided by Django itself, such as the built-in User model, which is a very common model to extend.

Next, we will practice extending our practice model called engine2 and then extend the Django User model, turning it into the Seller model. This would make the Seller object related to a Vehicle and also act as a User, provided with permission-based roles and permission group capabilities.

Extending basic model classes

Extending regular model classes is pretty easy to do. Follow these steps to extend the engine2 practice class:

1. In your /chapter_3/models.py file, in the class named engine2, keep the name field as is and then add a new field called vehicle_model...