Understanding Abstraction in OOP

Hello, fellow coder! Today, we'll decode Python's Abstraction principle, a powerful tool in Object-Oriented Programming. Abstraction is our superhero against the seemingly overwhelming complexity, revealing only the necessary details. Are you ready for the fun?

Imagine Abstraction as a superboat, stripping off the complexities and giving you just the essentials to operate effectively. It’s not about understanding all the intricate details; it is about focusing on what truly matters. Consider it this way - to drive a car, you only engage with its external controls while the complex workings beneath remain hidden.

Abstraction in Python

In Python, objects are defined through classes. Every class serves as a preliminary blueprint for an object. It stipulates both the data (attributes) and their potential behaviors (methods). Similar to a car’s control panel, an object's class provides a user-friendly interface, concealing the complex mechanics within.

When utilizing a Python list, you employ methods like append(), remove(), and sort(). You do so without needing to comprehend how Python manages the list's memory space. The internal workings are abstracted.

Python's Abstract Base Classes

In Python, classes that possess abstract methods are termed "abstract base classes" (ABC). Python's abc module aids in defining these abstract base classes. An ABC is akin to the pearl inside an oyster, housing at least one abstract method. Each abstract method in an ABC awaits its implementation in subclasses.

Consider this simple example:

from abc import ABC, abstractmethod

class AbstractClassExample(ABC):
    # This method is waiting to be overridden
    @abstractmethod
    def do_something(self):
        pass

frame = AbstractClassExample() # Will raise TypeError

As you can see, you cannot instantiate an abstract class, as it's just a skeleton for the future class that will be derived from it. The @abstractmethod annotation marks a method as abstract, meaning that's a property/behavior that this class supports, but it has not been implemented yet.

Real-world Example of Abstraction in Python

For instance, when crafting a doodling app that handles shapes, you would define an abstract base class called Shape. It would have area and perimeter as its abstract methods:

class Shape(ABC):
    @abstractmethod
    def area(self):
        pass

    @abstractmethod
    def perimeter(self):
        pass

To create actual shapes like Rectangle and Circle, you would inherit traits from Shape and define area and perimeter.

class Rectangle(Shape):
    def __init__(self, width, height):
        self.width = width
        self.height = height

    def area(self):
        return self.width * self.height

    def perimeter(self):
        return 2 * (self.width + self.height)

class Circle(Shape):
    def __init__(self, radius):
        self.radius = radius

    def area(self):
        return 3.14 * (self.radius)**2

    def perimeter(self):
        return 2 * 3.14 * self.radius

rectangle = Rectangle(2, 3) # A rectangle with sides 2 and 3
print(rectangle.area()) # Prints: 6
print(rectangle.perimeter()) # Prints: 10

circle = Circle(5) # A circle with a radius of 5
print(circle.area()) # Prints: 78.5
print(circle.perimeter()) # Prints: 31.4

Shape classes provide an abstraction layer, reducing the knowledge you require to calculate the area and perimeter.

Sign up
Join the 1M+ learners on CodeSignal
Be a part of our community of 1M+ users who develop and demonstrate their skills on CodeSignal