Question on book <Dive into Design Patterns>, Inheritance

Question regarding the example for Decorator in Python's class-static variable (_component)

The typescript example of Prototype seems to have incorrect code

Write a book about unit testing with this incredible format you use

Запитання, щодо імплементації патерну проектування Singleton на мові програмування Python

Rust singleon - with Map

Possible error

There should be one obvious way to do it - CoR

Thanks Alexander

Design patterns for Game engines