Python Assignment Questions: Object-Oriented Programming

Note

These assignments test your understanding of classes, objects, constructors, encapsulation, inheritance, polymorphism, and abstraction. Write clean, well-documented code with meaningful variable names.

Classes and Objects

1. Library Book Management

Create a class Book with attributes: title, author, ISBN, and availability status. Implement methods to: - Display book information - Mark book as borrowed - Mark book as returned - Check if book is available

Hint: Use a boolean attribute is_available to track status. Initialize it to True in the constructor.

2. Student Grade Calculator

Create a class Student with name, roll number, and a list to store subject marks. Implement methods to: - Add marks for a subject (validate 0-100 range) - Calculate total marks - Calculate average marks - Determine grade (A: ≥90, B: ≥75, C: ≥60, D: ≥40, F: <40)

Hint: Store marks as a list of dictionaries: [{'subject': 'Python', 'marks': 85}]. Use the average for grade calculation.

3. Shopping Cart System

Create a class ShoppingCart that manages items in a shopping cart. Implement methods to: - Add item with name, price, and quantity - Remove item by name - Update quantity of an item - Calculate total price - Display all items with subtotals

Hint: Use a list to store items as dictionaries. For total price: sum of (price × quantity) for all items.

Constructors and Destructors

4. Bank Account with Transaction History

Create a class BankAccount with constructor accepting account number, holder name, and initial balance. Implement: - Deposit method (adds to balance and records transaction) - Withdraw method (checks sufficient balance, deducts, records transaction) - Display transaction history - Destructor that prints final balance when account is closed

Hint: Use a list to store transactions with timestamp (you can use simple counter). Store as {'type': 'deposit', 'amount': 1000}.

5. Temperature Monitor with Statistics

Create a class TemperatureMonitor that tracks temperature readings. Constructor accepts location name. Implement: - Add temperature reading - Get average temperature - Get maximum and minimum temperatures - Reset all readings - Destructor showing total readings recorded

Hint: Store temperatures in a list. Use max() and min() built-in functions. Count readings using len().

6. Product Inventory Manager

Create a class Product with constructor for product name, SKU, price, and initial stock. Implement: - Add stock (increment quantity) - Remove stock (decrement if sufficient) - Update price with validation (must be positive) - Calculate total inventory value (price × quantity) - Display product details with stock status

Hint: Use default parameter for initial stock (default=0). Total value = self.price * self.stock_quantity.

Encapsulation

7. Secure Email Account

Create a class EmailAccount with private attributes for email address and password. Implement: - Constructor to set email and password - Method to verify password - Method to change password (requires old password verification) - Method to send email (requires password verification) - Property to get email address (read-only)

Hint: Use __email and __password for private attributes. Use @property for read-only email access.

8. Student Record System with Privacy

Create a class StudentRecord with private attributes for student ID, name, and grades. Implement: - Constructor with validation (ID must be non-empty, grades 0-100) - Getter and setter for name using @property - Method to add grade with validation - Method to get average (but not expose individual grades directly) - Property to get student ID (read-only)

Hint: Use __id, __name, __grades as private. Validate in setter: if 0 <= grade <= 100.

9. ATM with Daily Withdrawal Limit

Create a class ATMAccount with private balance and daily withdrawal limit. Implement: - Constructor to set initial balance and limit - Method to withdraw (check balance and daily limit) - Method to deposit - Method to reset daily limit counter - Property to check balance (requires PIN validation) - Private method to validate PIN

Hint: Use __daily_withdrawn to track total withdrawn today. Reset with a method call at day end.

Inheritance

10. Employee Hierarchy

Create a base class Employee with name, ID, and base salary. Create child classes: - Manager: Add department and bonus attributes, override salary calculation to include bonus - Developer: Add programming language and project count, override salary with project-based calculation - Intern: Add stipend (fixed amount), override salary to return stipend only

Hint: Use super().__init__() in child constructors. Override a calculate_salary() method in each child class.

11. Vehicle Rental System

Create a base class Vehicle with brand, model, and daily_rent. Create child classes: - Car: Add number of seats, calculate rent with seat-based multiplier - Bike: Add engine capacity, calculate rent with capacity-based multiplier - Truck: Add cargo capacity, calculate rent with cargo-based multiplier Each should have a method to display rental information.

Hint: Base rent + (additional charge based on vehicle type). Use super().display() to show common info.

12. Shape Hierarchy with Area and Perimeter

Create a base class Shape with color attribute. Create child classes: - Rectangle: length and width attributes - Circle: radius attribute - Triangle: three sides attributes Each must implement area() and perimeter() methods.

Hint: Rectangle area = l×w, perimeter = 2(l+w). Circle area = πr², perimeter = 2πr. Use 3.14159 for π.

Polymorphism

13. Payment Processing System

Create an abstract base class Payment with abstract method process_payment(). Implement child classes: - CreditCard: Requires card number, CVV, expiry date - DebitCard: Requires card number, PIN - UPI: Requires UPI ID - Wallet: Requires wallet ID and balance check Each should implement process_payment() differently.

Hint: Use from abc import ABC, abstractmethod. Create a function that accepts any Payment object and calls process_payment().

14. Document Converter

Create an abstract class Document with abstract methods open() and save(). Implement: - PDFDocument: Specific open/save for PDF - WordDocument: Specific open/save for Word - TextDocument: Specific open/save for Text Create a function that processes any document type.

Hint: Each document type should print different messages in open() and save() methods showing format-specific operations.

15. Notification System with Multiple Channels

Create an abstract class Notification with abstract method send(message, recipient). Implement: - EmailNotification: Send via email - SMSNotification: Send via SMS - PushNotification: Send push notification - WhatsAppNotification: Send via WhatsApp Create a function to send the same message through multiple channels.

Hint: Store notification objects in a list and iterate. Each send() should print how the message is delivered.

Advanced OOP

16. Library Management System

Create a complete library system with: - Abstract class LibraryItem with title, ID, and abstract methods - Classes: Book, Magazine, DVD inheriting from LibraryItem - Class Member with name, ID, and borrowed items list - Class Library managing items and members Implement borrowing, returning, and searching functionality.

Hint: Use composition (Library contains items and members). Track borrowed items per member. Check availability before borrowing.

17. Banking System with Multiple Account Types

Create a banking system with: - Abstract class Account with abstract method calculate_interest() - SavingsAccount: Fixed interest rate, minimum balance requirement - CurrentAccount: No interest, overdraft facility - FixedDeposit: High interest, locked period, penalty for early withdrawal - Class Bank managing multiple accounts Implement deposit, withdrawal, interest calculation, and account statements.

Hint: Use inheritance for account types. Override calculate_interest() in each. Bank class should maintain a list of accounts.

18. E-Commerce Product Catalog

Create a product catalog system with: - Abstract class Product with abstract method calculate_price() - Electronics: warranty period affects price - Clothing: size and brand affect price - Grocery: expiry date affects price (discount near expiry) - Class ShoppingCart with multiple products - Implement discount coupons (percentage or fixed amount) Calculate final bill with all discounts.

Hint: Use polymorphism for price calculation. Cart stores list of products. Apply discounts at cart level.

Operator Overloading

19. Complex Number Operations

Create a class ComplexNumber representing complex numbers (a + bi). Overload: - + for addition: (a + bi) + (c + di) = (a+c) + (b+d)i - - for subtraction - * for multiplication: (a + bi)(c + di) = (ac - bd) + (ad + bc)i - == for equality comparison - __str__ for display format “a + bi”

Hint: Use __add__, __sub__, __mul__, __eq__, __str__. For multiplication, expand (a+bi)(c+di).

20. Time Duration Calculator

Create a class Duration representing time in hours and minutes. Overload: - + to add two durations - - to subtract durations - > and < for comparison - __str__ for display as “Xh Ym” Handle minute overflow (60 minutes = 1 hour).

Hint: Convert to total minutes for comparison. For addition: add minutes, handle overflow with // and %.

Real-World Projects

21. Hotel Booking System

Create a complete hotel booking system with: - Abstract class Room with room number, type, and price - Room types: StandardRoom, DeluxeRoom, Suite (different prices and amenities) - Class Guest with personal details - Class Booking linking guest, room, check-in/out dates - Class Hotel managing rooms and bookings Implement booking, cancellation, and availability checking.

Hint: Use inheritance for room types. Track booking dates to check availability. Calculate total cost based on number of nights.

22. University Management System

Create a university system with: - Class Person as base (name, ID, contact) - Student class: courses enrolled, grades - Professor class: courses teaching, department - Course class: course code, name, professor, enrolled students - Department class: managing courses and faculty Implement enrollment, grade assignment, and course management.

Hint: Use inheritance from Person. Use composition (Course contains professor and students). Maintain bidirectional relationships.

23. Online Food Delivery System

Create a food delivery system with: - Abstract class MenuItem with abstract method prepare() - Menu items: Pizza, Burger, Beverage with different preparation - Class Order containing multiple menu items - Class Customer with address and order history - Class DeliveryPerson with current orders - Calculate total bill with taxes and delivery charges Implement order placement, preparation tracking, and delivery.

Hint: Use polymorphism for prepare(). Order contains list of items. Calculate bill: sum of items + tax (18%) + delivery (₹50).

Testing and Validation

24. Create Test Cases

For any of the above assignments (your choice), create a separate test program that: - Creates multiple objects with different data - Tests all methods thoroughly - Tests edge cases (invalid inputs, boundary values) - Prints results in organized format - Verifies expected behavior

Hint: Test with valid and invalid inputs. Check boundary conditions (empty lists, zero values, negative numbers).

25. Documentation and Code Quality

Take your implementation of assignment 16, 17, or 18 and: - Add comprehensive docstrings to all classes and methods - Add inline comments for complex logic - Use meaningful variable names - Organize code with proper spacing and structure - Create a README explaining how to use the system

Hint: Use triple quotes for docstrings: """This method does...""". Explain parameters, return values, and exceptions.

Submission Guidelines

Note

  • Test your code thoroughly before submission

  • Use meaningful variable and method names

  • Add comments for complex logic

  • Handle exceptions where appropriate

  • Include example usage/test cases for each program

  • Ensure code follows Python naming conventions (PEP 8)

Evaluation Criteria

Your assignments will be evaluated on:

  1. Correctness: Does the code work as expected?

  2. OOP Principles: Proper use of classes, inheritance, encapsulation, etc.

  3. Code Quality: Clean, readable, well-organized code

  4. Documentation: Clear comments and docstrings

  5. Testing: Comprehensive test cases

  6. Error Handling: Appropriate validation and exception handling