Abstraction is a fundamental concept in object-oriented programming that allows a developer to focus on the essential features of an object, while ignoring the details of its implementation. In Python, abstraction is achieved by using abstract classes and abstract methods.

An abstract class is a class that cannot be instantiated, and is meant to be subclassed by other classes. It is used to define a common interface for a group of related classes, without specifying the implementation details. An abstract class is declared using the abc module in Python, and is defined by inheriting from the ABC class.

Here is an example of an abstract class in Python:

from abc import ABC, abstractmethod

class Shape(ABC):
    def area(self):

class Rectangle(Shape):
    def __init__(self, length, width):
        self.length = length
        self.width = width
    def area(self):
        return self.length * self.width

rectangle = Rectangle(5, 10)
print(rectangle.area()) # Output: 50

In this example, the Shape class is an abstract class that defines the area() method as an abstract method using the @abstractmethod decorator. This means that any subclass of Shape must implement the area() method. The Rectangle class is a subclass of Shape that implements the area() method to calculate the area of a rectangle.

By using abstraction, we can write code that is more flexible, maintainable, and reusable. It also helps to reduce complexity and improve code readability by separating the interface from the implementation details.