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Classes and Objects

Python uses classes to create user-defined data types. A class is a blueprint for creating objects. Objects are instances of a class.

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

    def bark(self):
        print("Woof!")

my_dog = Dog("Buddy", "Golden Retriever")  #Creating an object (instance of Dog class)
print(my_dog.name) # Accessing attributes
my_dog.bark() # Calling a method

Constructors Methods Attributes

Classes have:

• Attributes: These are variables that hold data associated with an object (e.g., my_dog.name, my_dog.breed).
• Methods: These are functions that operate on the object’s data (e.g., my_dog.bark()). Methods always take self as their first parameter, which refers to the instance of the class.

Key Concepts:

• __init__ method: This is a special method called the constructor. It’s automatically called when you create a new object. It’s used to initialize the object’s attributes.
• self parameter: Refers to the instance of the class. It allows methods to access and modify the object’s attributes.

Related Notes:

• Inheritance
• Polymorphism
• Encapsulation
• Abstract Classes
• Multiple Inheritance
• Method Resolution Order (MRO)
• Private and Protected Members