How are key object-oriented programming concepts implemented in Python?

In Python, the key concepts of object-oriented programming (OOP) are implemented as follows:

• Classes and objects: a class is a template for creating objects.

• Encapsulation: hiding internal implementation through conventions (e.g., _protected and __private attributes).

• Inheritance: creating a new class based on an existing one.

• Polymorphism: the ability to use objects of different classes through a common interface.

Example:

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

    def speak(self):
        pass  # base method

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

class Cat(Animal):
    def speak(self):
        return f'{self.name} says: Meow!'

animals = [Dog('Sharik'), Cat('Murka')]
for animal in animals:
    print(animal.speak())

This demonstrates inheritance (Dog and Cat from Animal), polymorphism (different implementations of the speak method), and encapsulation through class attributes.