Skip to main content

Multiple Inheritance in Python

 

Learning Sections          show

Multiple Inheritance in Python

Multiple inheritance is a feature in object-oriented programming where a class can inherit attributes and methods from more than one base class. This allows for the combination of behaviors and properties from multiple classes into a single derived class, enhancing code reuse and modularity.

Example of Multiple Inheritance

Let's look at an example to understand how multiple inheritance works in Python.


# Define the first base class
class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = age

    def display_person_info(self):
        return f"Name: {self.name}, Age: {self.age}"

# Define the second base class
class Employee:
    def __init__(self, employee_id, position):
        self.employee_id = employee_id
        self.position = position

    def display_employee_info(self):
        return f"Employee ID: {self.employee_id}, Position: {self.position}"

# Define the derived class
class Manager(Person, Employee):
    def __init__(self, name, age, employee_id, position, department):
        Person.__init__(self, name, age)
        Employee.__init__(self, employee_id, position)
        self.department = department

    def display_manager_info(self):
        return f"{self.display_person_info()}, Employee ID: {self.employee_id}, Position: {self.position}, Department: {self.department}"

# Create an instance of the derived class
manager = Manager("Alice", 35, "M123", "Project Manager", "IT")
print(manager.display_manager_info())  
    # Output: Name: Alice, Age: 35, Employee ID: M123, Position: Project Manager, Department: IT
Explanation:

In this example, we have three classes: Person, Employee, and Manager. The Person and Employee classes are base classes, each with its own initializer method and methods to display information. The Manager class is the derived class that inherits from both Person and Employee, combining their attributes and methods. The __init__ method of the Manager class initializes attributes from both base classes and adds a new attribute department.

Advantages of Multiple Inheritance
  • Code Reusability: Allows the reuse of code from multiple base classes, reducing duplication and enhancing modularity.
  • Combination of Features: Combines features and behaviors from multiple classes, creating more complex and feature-rich derived classes.
  • Flexibility: Provides flexibility in designing class hierarchies, allowing for more diverse and adaptable designs.
Disadvantages of Multiple Inheritance
  • Complexity: Increases complexity in the class hierarchy, making it harder to understand and maintain.
  • Ambiguity: Can lead to ambiguity when methods or attributes with the same name are present in multiple base classes, requiring careful resolution using the method resolution order (MRO).
  • Tight Coupling: Creates tighter coupling between classes, making changes in base classes potentially more impactful on derived classes.
Method Resolution Order (MRO)

In Python, the order in which base classes are searched when looking for a method or attribute is determined by the Method Resolution Order (MRO). The mro() method can be used to display the MRO of a class.


print(Manager.mro())  
    # Output: [<class 'Manager'>, <class 'Person'>, <class 'Employee'>, <class 'object'>]
Key Points
  • Multiple inheritance allows a derived class to inherit from more than one base class.
  • Provides enhanced code reuse, modularity, and flexibility in designing class hierarchies.
  • Introduces complexity and potential ambiguity that need to be carefully managed.
Labels:

Popular posts from this blog

Introduction to OOPs in Python

  Learning Sections          show Introduction to Object-Oriented Programming (OOP) Object-Oriented Programming (OOP) is a programming paradigm that organizes software design around objects rather than actions and data rather than logic. It revolves around the concept of "objects", which are instances of classes. These objects encapsulate data, in the form of attributes or properties, and behaviors, in the form of methods or functions. OOP promotes modularity, reusability, and extensibility in software development. Key Concepts of OOP: Class: A class is a blueprint or template for creating objects. It defines the attributes (data) and methods (functions) that will characterize any object instantiated from that class. Object: An object is an instance of a class. It is a concrete realization of the class blueprint, containing actual values instead of placeholders for attributes. Encapsulation: Encapsulation is ...
Read more

Classes and Objects in Python

  Learning Sections          show Classes and Objects in Python In Python, a class is a blueprint for creating objects. An object is an instance of a class. Classes allow you to logically group data and functions in a way that is easy to manage and reuse. 1. Defining a Class To define a class in Python, you use the class keyword followed by the class name and a colon. Inside the class, you can define attributes and methods. Example: # Define a class class Person : # Class attribute species = 'Human' # Class method def greet ( self ): return 'Hello, I am a person.' # Create an object of the class person1 = Person () # Access class attribute print ( person1 . species ) # Output: Human # Call class method print ( person1 . greet ()) # Output: Hello, I am a person. 2. Creating Objects To create an object of a class, you simply call the class name followed by paren...
Read more

Exception Handling in Python

  Learning sections          show Exception Handling in Python Exception handling in Python is done through the use of try , except , else , and finally blocks. This allows you to catch and handle errors gracefully. Below are some examples and explanations: 1. Basic Try-Except The try block lets you test a block of code for errors. The except block lets you handle the error. # Example of basic try-except try : result = 10 / 0 except ZeroDivisionError : print ( "Cannot divide by zero!" ) # Output: # Cannot divide by zero! 2. Handling Multiple Exceptions You can catch multiple exceptions by specifying multiple except blocks. # Example of handling multiple exceptions try : result = 10 / 0 except ZeroDivisionError : print ( "Cannot divide by zero!" ) except TypeError : print ( "Invalid operation!" ) # Output: # Cannot divide by zero! 3. Using Else The e...
Read more