Object Oriented Programming in Python

This file contains basic and advanced about Object Oriented Programming in Python. Some of the below concepts has been discussed -->

1. Object and Classes
2. Encapsulation
3. Inheritence
4. Abstruct Class In # main.py file , you will get most of the things .

2. SOLID Principles

   • Single Responsibility Principle (SRP): A class should have one and only one reason to change.
   • Open/Closed Principle (OCP): Software entities should be open for extension but closed for modification.
   • Liskov Substitution Principle (LSP): Derived classes should be substitutable for their base classes.
   • Interface Segregation Principle (ISP): Clients should not be forced to depend on methods they do not use.
   • Dependency Inversion Principle (DIP): High-level modules should not depend on low-level modules; both should depend on abstractions.

3. Design Patterns

   • Singleton Pattern: Ensures a class has only one instance and provides a global point of access to it. Both metaclass-based and __new__-based implementations are demonstrated.
   • Strategy Pattern: Enables selecting an algorithm's behavior at runtime. Examples include different shipping cost strategies based on flat rate and weight-based calculations.