In this course, you’ll explore object-oriented programming in Python by building a social media app using classes, inheritance, and encapsulation.

python12.tar.gz

Python3.12

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This course offers a comprehensive introduction to object-oriented programming (OOP) in Python, a paradigm shift from procedural programming after you’ve learned the language basics.

Starting with the fundamentals of classes, objects, and methods, you’ll learn how to structure code for better organization, scalability, and readability. You’ll explore essential OOP concepts like encapsulation, inheritance, and polymorphism through hands-on examples, including a micro social media platform called Chirpy. You’ll practice creating private data attributes to protect your code from unintended interference, supporting the principle of abstraction and encapsulation.

By the end, you’ll develop a solid understanding of Python’s OOP features and gain confidence in designing and building real-world applications that are easy to extend. This journey prepares you to tackle advanced topics and larger projects, strengthening your foundation in Python’s object-oriented best practices.

Object-Oriented Programming in Python

from datetime import datetime, timedelta  

class Vehicle:
    def __init__(self, brand, model, vehicle_type):
        self.brand = brand
        self.model = model
        self.vehicle_type = vehicle_type
        self.is_rented = False
        self.rental_due_date = None

    def rent(self, customer):
        # Allow a customer to rent the vehicle if available
        if not self.is_rented:
            self.is_rented = True
            self.rental_due_date = datetime.now() + timedelta(days=7)
            customer.rented_vehicle = self
            print("%s rented %s %s, due back on %s." % (customer.name, self.brand, self.model, self.rental_due_date.date()))
        else:
            print("%s %s is already rented." % (self.brand, self.model))

    def return_vehicle(self):
        # Return the vehicle and clear the due date
        self.is_rented = False
        self.rental_due_date = None
        print("%s %s has been returned." % (self.brand, self.model))

    def __str__(self):
        return "%s %s (%s)" % (self.brand, self.model, self.vehicle_type)

from vehicle import Vehicle

class Truck(Vehicle):
    """A Truck requires a truck license to rent."""
    def rent(self, customer):
        # Prevent renting unless the customer has a truck license
        if customer.has_truck_license:
            Vehicle.rent(self, customer)
        else:
            print("%s cannot rent %s %s without a truck license." % (customer.name, self.brand, self.model))

class Customer:
    def __init__(self, name, has_truck_license=False):
        self.name = name
        self.has_truck_license = has_truck_license
        self.rented_vehicle = None

    def rent_vehicle(self, vehicle):
        # Rent a vehicle if eligible (only one at a time)
        if self.rented_vehicle:
            print("%s already has a rented vehicle and must return it first." % self.name)
        else:
            vehicle.rent(self)

    def return_vehicle(self):
        # Return the currently rented vehicle
        if self.rented_vehicle:
            self.rented_vehicle.return_vehicle()
            self.rented_vehicle = None
        else:
            print("%s has no rented vehicle to return." % self.name)

class RentalService:
    def __init__(self):
        self.vehicles = [ ]   # Stores Vehicle objects
        self.customers = [ ]  # Stores Customer objects

    def add_vehicle(self, vehicle):
        # Add a vehicle to the rental system
        self.vehicles.append(vehicle)
        print("Vehicle %s %s added to the rental service." % (vehicle.brand, vehicle.model))

    def list_available_vehicles(self):
        # List all vehicles that are not currently rented
        available = [v for v in self.vehicles if not v.is_rented]
        if available:
            print("\nAvailable Vehicles:")
            for v in available:
                print(v)
        else:
            print("No vehicles available.")

    def add_customer(self, customer):
        # Add a customer to the system
        self.customers.append(customer)
        print("Customer %s added to the rental service." % customer.name)

from rental_service import RentalService 
from vehicle import Vehicle
from truck import Truck
from customer import Customer

rental_service = RentalService()

# Add vehicles
car = Vehicle("Toyota", "Camry", "Car")
motorcycle = Vehicle("Honda", "CBR500R", "Motorcycle")
truck = Truck("Ford", "F-150", "Truck")
rental_service.add_vehicle(car)
rental_service.add_vehicle(motorcycle)
rental_service.add_vehicle(truck)

print("\n")

# Add customers
alice = Customer("Alice")
bob = Customer("Bob", has_truck_license=True)
rental_service.add_customer(alice)
rental_service.add_customer(bob)

print("\n")

# Renting vehicles
alice.rent_vehicle(truck)   # Should fail
bob.rent_vehicle(truck)     # Should succeed
alice.rent_vehicle(car)  # Should succeed 

print("\n")

# Returning vehicle and renting again
alice.return_vehicle()
alice.rent_vehicle(motorcycle)  # Now should succeed


# List available vehicles after operations
rental_service.list_available_vehicles()

import React from 'react';
import { shallow, configure } from 'enzyme';
import Adapter from 'enzyme-adapter-react-16';

configure({ adapter: new Adapter() });

import HelloWorld from './app';

var TestResult = function() {
    this.succeeded = false;
    this.reason = "";
    this.input = "";
    this.expected_output = "";
    this.actual_output = "";
}

export const executeTests = function() {

  var results = [];

  result = new TestResult();
  result.input = 'HelloWorld Component';
  result.expected_output = "span containing text 'Hello World'"

  let wrapper = shallow(<HelloWorld />);

  // Call your Challenge function here.

  let type = wrapper.type();
  let testSuccessful = true;
  let failureReason;

  if (type !== 'span') {
    testSuccessful = false;
    failureReason = "You need to render exactly one span HTML element";
  } else if (wrapper.props().children != "Hello World") {
     testSuccessful = false;
     failureReason = "You have rendered wrong message in your span element";
  }

  result.actual_output = wrapper.html();

  if (testSuccessful) {
    result.succeeded = true;
    result.reason = "Succeeded"
  } else {
    result.succeeded = false;
    result.reason = failureReason;
  }

  results.push(result);

  return results;
}


Introduction to OOP

Core Classes and Objects

Organize and Protect Data

Enhance Functionality with Advanced OOP Concepts

Code Organization and Final Review

Conclusion

Solution: The Final Challenge