OOP Basics

Classes, objects, attributes, and methods

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Explanation

Object-Oriented Programming organizes code around objects — bundles of data (attributes) and behavior (methods).

python

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

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

fido = Dog("Fido") # create instance print(fido.bark()) # Fido says Woof! ```

Key concepts:

class — blueprint for creating objects
__init__ — constructor, called when creating an instance
self — refers to the current instance
Inheritance — a class can extend another class

Examples

Inheritance

Cat inherits from Animal and overrides the speak method

class Animal:
    def __init__(self, name):
        self.name = name
    def speak(self):
        return "..."

class Cat(Animal):
    def speak(self):
        return f"{self.name} says Meow"

c = Cat("Whiskers")
print(c.speak())  # Whiskers says Meow

Unlocks

Exceptions & Error Handling OOP Advanced