We can extend a number of ABCs to create new kinds of collections. The ABCs provide us with design guidelines to extend the built-in containers. These allow us to fine-tune the features or radically define new data structures that fit our problem domain more precisely.

We'll look at the basics of ABC for container classes. There are a fairly large number of abstractions that are used to assemble the Python built-in types, such as list, tuple, dict, set, and frozenset.

We'll review the variety of special methods that are involved in being a container and offering the various features of containers. We'll split these into the core container methods, separate from more specialized sequence, map, and set methods.

We'll address extending built-in containers to add features. We'll also look at wrapping built-in containers and delegating methods through the wrapper to the underlying container.

Finally, we'll look at building entirely new containers. This...