Exploring the Basics of Object-Oriented Programming in Python: Part 1

Object-Oriented Programming (OOP) is a popular programming paradigm that has been widely used in the development of software applications. OOP enables us to organize code into reusable and self-contained objects that have properties and methods to perform specific tasks. Python is one of the most widely used programming languages that supports OOP. In this article, we will discuss the basics of OOP in Python, including classes, objects, inheritance, polymorphism, encapsulation, and abstraction.

Classes

In OOP, a class is a blueprint or a template that defines the properties and methods of an object. In Python, we can define a class using the?class?keyword followed by the name of the class. For example, let's create a simple class called?Person:

class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = age
    
    def say_hello(self):
        print("Hello, my name is " + self.name + " and I am " + str(self.age) + " years old.")        

In the above code, we define a class called?Person?that has two properties (name?and?age) and one method (say_hello). The?__init__?method is a special method in Python that is called when an object is instantiated from the class. The?self?parameter refers to the object being created.

Objects

An object is an instance of a class. We can create an object of a class by calling the class name followed by parentheses. For example, let’s create an object of the?Person?class

person1 = Person("John", 30)        

In the above code, we create an object called?person1?of the?Person?class with the name "John" and age 30.

Inheritance

Inheritance is a mechanism in OOP that allows us to define a new class based on an existing class. The new class is called the derived class, and the existing class is called the base class. The derived class inherits all the properties and methods of the base class, and we can add new properties and methods to the derived class as well. For example, let’s create a new class called?Student?that inherits from the?Person?class:

class Student(Person):
    def __init__(self, name, age, grade):
        super().__init__(name, age)
        self.grade = grade
    
    def say_hello(self):
        print("Hello, my name is " + self.name + " and I am a student in grade " + str(self.grade) + ".")        

In the above code, we define a new class called?Student?that inherits from the?Person?class. The?super()?function is used to call the?__init__?method of the base class, and we add a new property (grade) and a new method (say_hello) to the derived class.

Polymorphism

Polymorphism is a concept in OOP that allows us to use the same method or function with different types of objects. For example, let’s create a function called?introduce?that takes an object of the?Person?class as a parameter and calls the?say_hello?method:

def introduce(person):
    person.say_hello()        

In the above code, we define a function called?introduce?that takes an object of the?Person?class as a parameter and calls the?say_hello?method. We can use this function with objects of both the?Person