Python 3 Object-oriented Programming – Second Edition

A subclass is also said to be derived from its parent class or that the subclass extends the parent.

As discussed in Chapter 1, Object-oriented Design, inheritance allows us to create is a relationships between two or more classes, abstracting common logic into superclasses and managing specific details in the subclass.

Minimizing the amount of code can often make a program easier to read, but do not blindly assume this is the case.

In contrast, the object-oriented code is relatively self-documenting, we just have to look at the list of methods and their parameters to know what the object does and how to use it.

There is no reason to add an extra level of abstraction if it doesn't help organize our code.

Remember, objects are things that have both data and behavior.

On the other hand, if we are working only with behavior, but no stored data, a simple function is more suitable.

If we are working only with data, we are often better off storing it in a list, set, dictionary, or some other Python data structure (which we'll be covering thoroughly in Chapter 6, Python Data Structures).

Remember to design and document any self-raised exceptions as part of the API, or they won't know whether or how to handle them!

If you've never dealt with exceptions before, the first thing you need to do is look at any old Python code you've written and notice if there are places you should have been handling exceptions.