Inheritance

Inheritance is a fundamental pillar of object-oriented programming. It allows you to create new classes based on existing classes, reusing and extending their functionality. This way, you can model “is a” relationships (for example, a Dog is an Animal).

---

Why use inheritance?

• Code reuse: Avoid repeating common attributes and methods.
• Organization: Allows structuring logical hierarchies between classes.
• Extension: You can add or modify behaviors in subclasses.

---

Basic syntax

To create a class that inherits from another, simply indicate the base class in parentheses:

class BaseClass:
    # attributes and methods

class SubClass(BaseClass):
    # new attributes and methods

---

Simple example

Suppose you have an Animal class and you want to create a Dog class that inherits from it:

Basic inheritance

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

def speak(self):
print('Makes a sound')

class Dog(Animal):
def speak(self):
print(f'{self.name} says: Woof!')

my_dog = Dog('Rex')
my_dog.speak()  # Rex says: Woof!

In this example, Dog inherits the name attribute and the speak method from Animal, but redefines it to customize the behavior.

---

Using super()

You can call methods of the base class using super(). This is useful for extending functionality without completely replacing it.

Using super()

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

def describe(self):
print(f'I am an animal called {self.name}')

class Cat(Animal):
def describe(self):
super().describe()
print('And I am a cat.')

g = Cat('Michi')
g.describe()

Output:

I am an animal called Michi
And I am a cat.

---

Multiple inheritance

In Python, a class can inherit from multiple classes at the same time:

class ClassA:
    pass

class ClassB:
    pass

class SubClass(ClassA, ClassB):
    pass

---

Summary

• Inheritance allows you to create classes that reuse and extend others.
• Use super() to access methods of the base class.
• You can redefine methods to customize the behavior in subclasses.
• Python allows multiple inheritance.

Ready to practice? Try creating a base class Vehicle and a subclass Car that adds its own method.