🏗️ Classes and Objects¶

Welcome to the world of Object-Oriented Programming (OOP)! OOP is a programming paradigm based on the concept of "objects", which can contain data (attributes) and code (methods).

📚 What are Classes and Objects?¶

Think of a Class as a blueprint or a template. It defines how something should look and behave. Think of an Object as a distinct instance created from that blueprint.

Real-world Analogy: - Class: The blueprint for a Car (specifies it has wheels, color, model, and can drive). - Object: A specific red Toyota Corolla in your driveway.

🛠️ Defining a Class¶

In Python, we use the class keyword.

class Dog:
    pass

🏭 Creating an Object¶

To create an object (instance), we call the class like a function.

my_dog = Dog()

🧬 Attributes and `init`¶

Attributes are variables that belong to an object. We usually initialize them in a special method called __init__ (the constructor).

self: Represents the specific instance of the class. It allows each object to store its own data.

class Dog:
    def __init__(self, name, breed):
        self.name = name   # Attribute
        self.breed = breed # Attribute

⚡ Methods¶

Methods are functions defined inside a class that describe the behaviors of an object.

class Dog:
    def __init__(self, name, breed):
        self.name = name
        self.breed = breed

    def bark(self):
        return f"{self.name} says Woof!"

📝 Example¶

# 1. Define the class
class Student:
    def __init__(self, name, grade):
        self.name = name
        self.grade = grade

    def introduce(self):
        print(f"Hi, I'm {self.name} and I got a {self.grade}!")

# 2. Create objects
student1 = Student("Alice", "A")
student2 = Student("Bob", "B")

# 3. Access attributes and methods
student1.introduce() # Output: Hi, I'm Alice and I got a A!
print(student2.name) # Output: Bob

🔍 Key Takeaways¶

Class: The template.
Object: The instance.
Attributes: Data stored in the object (self.variable).
Methods: Functions that operate on the object's data.
self: A reference to the current instance.

Next: Encapsulation