Core Python Programming (2nd Edition)

Functions versus methods

Methods are basically functions but tied to a specific class object type. They are defined as part of a class and are executed as part of an instance of that class.

Delegation

It makes no difference whether we use open() or capOpen() to read our file because in capOpen.py, we delegated all of the reading functionality to the Python system defaults, meaning that no special action is ever taken on reads. The same code would be executed, i.e., none of read(), readline(), or readlines() are overridden with any special functionality.