Day 25 – Method Overriding & super() Advanced
Project: Build a “Company Management App” that demonstrates advanced method overriding and the use of super() to extend parent behavior.
01. Learning Goal
By the end of this lesson, you will be able to:
- Redefine parent methods through overriding
- Extend parent behavior using
super() - Combine inheritance and customization effectively
- Write clean, maintainable OOP code with layered behavior
02. Problem Scenario
You’re designing a company management system where all employees share common behavior (work()),
but managers need to extend this logic with additional responsibilities.
This lesson focuses on how overriding and super() can help reuse and enhance parent functionality.
03. Step 1 – Method Overriding
A child class can redefine a method from its parent class.
The child’s method always takes priority.
class Animal:
def speak(self):
print("Generic animal sound.")
class Dog(Animal):
def speak(self): # Override
print("Woof!")
d = Dog()
d.speak() # Woof!
04. Step 2 – Why Use Overriding
Overriding lets you customize behavior in each subclass
while still sharing the same structure defined in the parent class.
05. Step 3 – Using super()
super() allows the child class to call a method from the parent class.
class Person:
def __init__(self, name):
self.name = name
def introduce(self):
print(f"My name is {self.name}")
class Student(Person):
def __init__(self, name, student_id):
super().__init__(name) # Call parent constructor
self.student_id = student_id
def introduce(self):
super().introduce() # Call parent method
print(f"My student ID is {self.student_id}")
s = Student("Sabin", "S123")
s.introduce()
Output:
My name is Sabin
My student ID is S123
06. Step 4 – Extending Behavior with super()
Instead of completely replacing a parent method,
you can extend it with additional functionality.
class Logger:
def log(self, message):
print(f"Log: {message}")
class FileLogger(Logger):
def log(self, message):
super().log(message) # Keep parent behavior
print(f"(Saved to file) {message}") # Add extra behavior
f = FileLogger()
f.log("System started")
Output:
Log: System started
(Saved to file) System started
07. Step 5 – Practice Examples
Example 1: Employee & Manager
class Employee:
def __init__(self, name):
self.name = name
def work(self):
print(f"{self.name} is working.")
class Manager(Employee):
def work(self):
super().work() # Extend base behavior
print(f"{self.name} is managing the team.")
m = Manager("Anna")
m.work()
Output:
Anna is working.
Anna is managing the team.
Example 2: Shape with Area
class Shape:
def area(self):
return 0
class Circle(Shape):
def __init__(self, r):
self.r = r
def area(self):
base = super().area() # Extend parent method
return base + 3.14 * self.r * self.r
c = Circle(5)
print("Circle area:", c.area())
Output:
Circle area: 78.5
08. Mini Project – Company Management App
Create a small system with multiple roles and extended behaviors.
class Employee:
def __init__(self, name):
self.name = name
def work(self):
print(f"{self.name} is performing general tasks.")
class Developer(Employee):
def work(self):
super().work()
print(f"{self.name} is writing Python code.")
class Manager(Employee):
def work(self):
super().work()
print(f"{self.name} is leading the project.")
employees = [Developer("Tom"), Manager("Anna")]
for e in employees:
e.work()
Output:
Tom is performing general tasks.
Tom is writing Python code.
Anna is performing general tasks.
Anna is leading the project.
09. Reflection
You have learned how to:
- Override parent methods to change or extend behavior
- Use
super()to reuse parent logic efficiently - Combine inheritance and extension to create flexible hierarchies
- Apply OOP best practices to real-world systems
Next → Day 26 – Encapsulation & Access Control
Learn how to protect object data and manage accessibility using private attributes and getters/setters.
