Difference between Method Overloading and Method Overriding in Python

Method Overloading and Method Overriding are two key concepts in object-oriented programming that help you manage methods in classes. Both concepts allow you to define methods in different ways, but they serve different purposes and behave differently. Method overloading provides flexibility with function signatures, and method overriding offers a way to customize or extend the behavior of inherited methods.

Method Overloading

Method Overloading is an example of Compile time polymorphism. In this, more than one method of the same class shares the same method name having different signatures. Method overloading is used to add more to the behavior of methods and there is no need of more than one class for method overloading.

Note: Python does not support method overloading. We may overload the methods but can only use the latest defined method.

Example: 

def add(datatype, *args): 
  
    # if datatype is int initialize answer as 0 
    if datatype =='int': 
        answer = 0
          
    # if datatype is str initialize answer as '' 
    if datatype =='str': 
        answer ='' 
  
    for x in args: 
  
        answer = answer + x 
  
    print(answer) 
  
# Integer 
add('int', 5, 6) 
  
# String 
add('str', 'Hi ', 'Geeks') 

11
Hi Geeks

Explanation: This code demonstrates method overloading in Python using *args. The add() function performs different operations based on the datatype argument. If datatype is 'int', it sums the integers in args. If datatype is 'str', it concatenates the strings in args. The function adapts to different input types, simulating overloading.

Method Overriding

Method overriding is an example of run time polymorphism. In this, the specific implementation of the method that is already provided by the parent class is provided by the child class. It is used to change the behavior of existing methods and there is a need for at least two classes for method overriding. In method overriding, inheritance always required as it is done between parent class(superclass) and child class(child class) methods. Example: 

class A:

    def fun1(self):
        print('feature_1 of class A')
        
    def fun2(self):
        print('feature_2 of class A')
    
class B(A):
    
    # Modified function that already exist in class A
    def fun1(self):
        print('Modified feature_1 of class A by class B')    
        
    def fun3(self):
        print('feature_3 of class B')
        
        
# Create instance
obj = B()
    
# Call the override function
obj.fun1()

Modified feature_1 of class A by class B

Explanation: This code demonstrates method overriding in Python. Class B inherits from class A and overrides the fun1() method. When fun1() is called on an instance of B, the overridden method in class B is executed instead of the original method in class A.

Difference between Method Overloading and Method Overriding in Python