OOP Practice Assignments in Python

This collection includes 21 hands-on exercises to master core Object-Oriented Programming (OOP) concepts using Python. Each exercise is standalone, with a dedicated file (e.g., exercise.py) containing functional code and explanatory comments.

🧠 Assignment Overview

1. Using self: Create Student class, use self to set name & marks, add display() to print details.
2. Using cls: Create Counter class, track object count with class variable & method using cls.
3. Public Variables/Methods: Create Car class with public brand & start(), access both externally.
4. Class Variables/Methods: Create Bank class with bank_name, add change_bank_name(cls, name) to update it for all instances.
5. Static Methods: Create MathUtils class with static method add(a, b) to return sum, no class/instance variables.
6. Constructors/Destructors: Create Logger class, print messages on object creation & destruction.
7. Access Modifiers: Create Employee class with public name, protected _salary, private __ssn, test access.
8. super(): Create Person class to set name, inherit Teacher, add subject, use super() to call parent constructor.
9. Abstract Classes: Use abc to create Shape with abstract area(), inherit Rectangle to implement area().
10. Instance Methods: Create Dog class with name & breed, add bark() to print message with name.
11. Class Methods: Create Book class with total_books, add increment_book_count() to increase count.
12. Static Methods: Create TemperatureConverter with static celsius_to_fahrenheit(c) to return Fahrenheit.
13. Composition: Create Engine & Car, pass Engine to Car during init, access Engine method via Car.
14. Aggregation: Create Department & Employee, use aggregation to store independent Employee in Department.
15. MRO & Diamond Inheritance: Create A, B, C, D classes, override show() in B & C, D inherits both, test MRO.
16. Function Decorators: Write log_function_call decorator to print message before say_hello() executes.
17. Class Decorators: Create add_greeting decorator to add greet() method to Person class.
18. Property Decorators: Create Product with private _price, use @property, @setter, @deleter to manage it.
19. callable() & call(): Create Multiplier, set factor, use __call__() to multiply input, test with callable().
20. Custom Exception: Create InvalidAgeError, raise in check_age(age) if age < 18, handle with try-except.
21. Custom Iterable: Create Countdown, take start number, use __iter__() & __next__() to count down to 0 in for-loop.

✅ How to Execute

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Enter the assignment folder,

   cd 01_Using_Self

Run the script with:

   python app.py

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📚 Prerequisites

Requires only a standard Python 3+ installation, no external libraries needed.

🎓 Learning Goals

These exercises aim to teach:

Object initialization and manipulation
Access and visibility rules
Inheritance and method behavior
Abstract design patterns
Decorator applications
Custom object capabilities
Dive into Python OOP and enjoy the journey! 🌟