Python Inheritance - ideasorblogs

What is Inheritance?

Inheritance is a way to create a new class that is a modified version of an existing class. The new class is called the subclass, and the existing class is the superclass.

The subclass inherits attributes and behavior methods from the superclass and can have additional attributes and behavior methods of its own. This allows you to reuse code and helps to keep your code organized and easy to maintain.

How to Use Inheritance in Python

To create a subclass in Python, you use the class keyword followed by the name of the subclass, and then include the name of the superclass in parentheses. For example:


class Subclass(Superclass):
    # code goes here

The subclass will inherit all of the attributes and behavior methods of the superclass. You can then add additional attributes and behavior methods to the subclass as needed.

Here is an example of a simple inheritance hierarchy in Python:


class Pet:
    def __init__(self, name, species):
        self.name = name
        self.species = species

    def make_sound(self):
        print("Some generic sound")


class Dog(Pet):
    def __init__(self, name, breed):
        super().__init__(name, species="Dog")
        self.breed = breed

    def make_sound(self):
        print("Bark")

In this example, the Pet class is the superclass, and the Dog class is the subclass. The Dog class inherits the name and species attributes from the Pet class, and has an additional attribute called breed. The Dog class also has its own version of the make_sound method, which overrides the version inherited from the Pet class.

Polymorphism

Polymorphism is the ability of a subclass to override or extend the behavior of a superclass. This is useful because it allows you to create subclasses that are specialized versions of the superclass, but that still retain the basic behavior of the superclass.

In the example above, the Dog class overrides the make_sound method of the Pet class. This means that when you call the make_sound method on a Dog object, it will use the version of the method defined in the Dog class, rather than the version inherited from the Pet class.

Here is an example of using polymorphism in Python:


pets = [Pet("Fluffy", "Cat"), Dog("Buddy", "Labrador")]

for pet in pets:
    pet.make_sound()

This code will output the following:


Some generic sound
Bark

The first Pet object uses the version of the make_sound method inherited from the Pet class, while the second Dog object uses the version of the make_sound method defined in the Dog class.