__getattr__ : Called only as a fallback when the requested attribute cannot be found through normal lookups.
: A strong hint to developers that the attribute is intended for internal use. It is not enforced by the interpreter.
: Deep understanding of what classes and instances truly are, including class data and function attributes. python 3 deep dive part 4 oop high quality
class A: pass class B(A): pass class C(A): pass class D(B, C): pass
: This is strictly an advanced course. You are expected to have a "strong working knowledge" of functional Python, closures, decorators, and generators. __getattr__ : Called only as a fallback when
Object-Oriented Programming (OOP) in Python goes far beyond defining classes and instantiating objects. To write truly high-quality, scalable, and maintainable Python code, you must understand the underlying mechanics of the language. This deep dive explores advanced OOP concepts in Python 3, focusing on dunder methods, descriptors, metaclasses, and design patterns. 1. The Python Object Model: Beyond Basic Classes
class User(JSONMixin): def (self, name): self.name = name : Deep understanding of what classes and instances
Descriptors, Metaprogramming (metaclasses), Slots, and Enumerations.
class Celsius: def __init__(self, temperature=0): self._temperature = temperature @property def temperature(self): return self._temperature @temperature.setter def temperature(self, value): if value < -273.15: raise ValueError("Temperature below absolute zero is impossible.") self._temperature = value
To ensure every class in a complex hierarchy executes its parent logic, always invoke initialization using super() . Avoid naming explicit parent classes inside methods.
Descriptors are objects that define __get__ , __set__ , or __delete__ . They are the mechanism behind properties, methods, and static methods. They allow you to define how attributes are accessed. Metaclasses