Object-Oriented Programming (OOP) in Python

In this article, we will explore Object-Oriented Programming (OOP) in Python from the ground up — starting with basic programming paradigms and gradually moving toward advanced concepts like abstract base classes, magic methods, dataclasses, and best practices.

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Object-Oriented Programming is one of the most powerful programming paradigms used in modern software development. Whether you’re preparing for interviews, building scalable applications, or aiming to write clean and reusable code, mastering OOP is essential.

1. Programming Paradigms
   - Procedural vs Object-Oriented Programming
   - Why OOP?
   - Real-world modeling concepts
   - OOP terminology (Class, Object, Attribute, Method)
2. Classes & Objects
   - Creating classes
   - Creating objects
   - __init__() constructor
   - self keyword
   - Instance variables
   - Instance methods
   - Object lifecycle
3. Class vs Instance Attributes
   - Class variables
   - Instance variables
   - Modifying class attributes
   - Namespaces
   - Memory structure overview
4. Magic (Dunder) Methods Basics
   - __str__
   - __repr__
   - __len__
   - __del__
   - __eq__
5. The 4 Pillars of OOP
   - Encapsulation
   - Abstraction
   - Inheritance
   - Polymorphism
6. Access Modifiers
   - Public
   - Protected
   - Private
   - Name mangling
   - Getters and Setters
   - @property decorator
7. Inheritance Deep Dive
   - Single Inheritance
   - Multiple Inheritance
   - Multilevel Inheritance
   - Hierarchical Inheritance
   - Method Overriding
   - super() function
   - MRO (Method Resolution Order)
8. Polymorphism
   - Method overriding
   - Duck typing
   - Operator overloading
   - Function overloading techniques in Python
9. Abstract Base Classes
   - abc module
   - @abstractmethod
   - Enforcing method implementation
10. Composition vs Inheritance
    - Has-A vs Is-A relationship
    - When to use composition
    - Dependency injection basics
11. Static & Class Methods
    - @staticmethod
    - @classmethod
    - Factory methods
12. Advanced Magic Methods
    - __add__
    - __sub__
    - __getitem__
    - __setitem__
    - __call__
    - __enter__ / __exit__
    - Custom iterators
13. Dataclasses
    - @dataclass
    - Field types
    - Default values
    - Frozen dataclasses
14. Object-Oriented Best Practices
    - Clean class design
    - Avoiding God objects
    - Code reusability techniques
    - Code smells in OOP
    - Refactoring techniques