Python Object Creation: Understanding __new__ and Immutability

Standard Python class creation works well for mutable objects, but when you need to extend built-in immutable types like strings or numbers, the standard approach fails. Mastering the object creation lifecycle is essential for building advanced, predictable data structures. Upon completion, you will gain a deep understanding of Python’s object lifecycle, allowing you to reliably subclass immutable types like int, str, and tuple, creating powerful, predictable custom data structures. What you'll learn: * Understand the critical difference between the object creation method (__new__) and the initialization method (__init__) * Apply __new__ correctly to subclass core immutable types such as float, str, and tuple * Practice creating custom, type-safe immutable classes that behave like built-in types * Learn how to handle object state and initialization arguments within the __new__ method * Configure alternative constructors and factory methods for flexible class instantiation * Apply modern Python type hints to ensure custom immutable classes are used safely throughout your codebase The course begins with foundational concepts of object instantiation and the Python data model, moves through practical examples of subclassing built-ins, and concludes with exercises on designing robust, production-ready custom types. This course is ideal for Python developers who understand basic classes and inheritance but want to master advanced object lifecycle management and custom type creation. No prior experience with the __new__ method is required. Start designing more powerful and predictable Python objects today.