Expert Python Programming - Third Edition

Adapter

The adapter pattern allows the interface of an existing class to be used from another interface. In other words, an adapter wraps a class or an object A so that it works in a context intended for a class or an object B.

Creating adapters in Python is actually very straightforward due to how typing in this language works. The typing philosophy in Python is commonly referered to as duck typing:

"If it walks like a duck and talks like a duck, then it's a duck!"

According to this rule, if the value for a function or method is accepted, the decision should not be based on its type but rather on its interface. So, as long as the object behaves as expected, that is, has proper method signatures and attributes, its type is considered compatible. ...