Mastering Object-oriented Python

Multi-strategy __init__()

We may have objects that are created from a variety of sources. For example, we might need to clone an object as part of creating a memento, or freeze an object so that it can be used as the key of a dictionary or placed into a set; this is the idea behind the set and frozenset built-in classes.

There are several overall design patterns that have multiple ways to build an object. One design pattern is complex __init__() that is called multi-strategy initialization. Also, there are multiple class-level (static) constructor methods.

These are incompatible approaches. They have radically different interfaces.

Tip

Avoid clone methods

A clone method that unnecessarily duplicates an object is rarely needed in Python. Using cloning ...