Continuing My Python OOP Journey

Understanding Inheritance in python

In my previous blog, I explored the fundamentals of Object-Oriented Programming (OOP) in Python, including classes, objects, constructors, instance methods, static methods, class methods, and getters & setters.

As I continued studying Python, I came across another important OOP concept called Inheritance. From that I understood how inheritance helps us write cleaner, reusable, and well-organized code.

What is Inheritance

Inheritance is an Object-Oriented Programming (OOP) concept that allows one class to inherit the attributes and methods of another class.

• The existing class is called the Parent (Base) Class.
• The new class is called the Child (Derived) Class.

The child class can use everything available in the parent class while also adding its own features.

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Single Inheritance

class Company:
    def company_info(self):
        print("Company Name is XYZ")


class Employee(Company):
    def employee_info(self):
        print("Employee Name is Rahul")


emp = Employee()

emp.company_info()
emp.employee_info()

Here one child class inherits from one parent class. Although company_info() is not defined inside Employee, it can still access the method because it inherits from the parent class.

Multiple Inheritance

class Company:

    def __init__(self, company_name):
        self.company_name = company_name

    def company_info(self):
        print(f"Company Name is {self.company_name}")


class Country:

    def __init__(self, country_name):
        self.country_name = country_name

    def country_info(self):
        print(f"Country Name is {self.country_name}")


class Employee(Company, Country):

    def __init__(self, employee_name, company_name, country_name):
        self.employee_name = employee_name

        Company.__init__(self, company_name)
        Country.__init__(self, country_name)

    def full_info(self):
        print(
            f"The employee {self.employee_name} lives in {self.country_name} and works for {self.company_name}"
        )


emp = Employee("Kavi", "XYZ", "USA")

emp.full_info()
emp.company_info()
emp.country_info()

In multiple inheritance allows child class to inherit from more than one parent class.

Multilevel Inheritance

class Company:

    def __init__(self, company_name):
        self.company_name = company_name

    def company_info(self):
        print(f"Company Name is {self.company_name}")


class Department(Company):

    def __init__(self, department_name, company_name):
        self.department_name = department_name
        Company.__init__(self, company_name)

    def department_info(self):
        print(
            f"The department is {self.department_name} of {self.company_name}"
        )


class Employee(Department):

    def __init__(self, employee_name, department_name, company_name):
        self.employee_name = employee_name
        Department.__init__(self, department_name, company_name)

    def employee_info(self):
        print(f"Employee Name is {self.employee_name}")


emp = Employee("Rahul", "HR", "ABC")

emp.employee_info()
emp.department_info()
emp.company_info()

Multilevel inheritance happens when a class inherits from another child class.

Inheritance is one of the core concepts of Object-Oriented Programming that makes Python more powerful and flexible. Whether it is Single Inheritance, Multiple Inheritance, or Multilevel Inheritance, each type helps us organize code and improve reusability.