Polymorphism in Python

1) Override a Method in Subclasses

Create a base class Animal with method sound(). Create subclasses Dog and Cat; override sound() so each prints a different string. Instantiate both and call sound().

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2) Polymorphism in a Loop

Define classes Car and Bike with .move() methods. In a list [Car(), Bike()], loop and call move() for each object.

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3) Same Method Name, Different Behavior

Create classes CalculatorV1 and CalculatorV2, both with add(a, b) but with different print styles. Call add() on both.

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4) Polymorphic Function

Write a function describe(obj) that calls obj.describe() for any object with that method.

Test with two different classes implementing describe().

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5) Duck Typing

Write a function make_sound(animal) that calls .sound(). Create two different classes with a sound() method (no inheritance) and pass them to make_sound().

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6) Built-in Polymorphism: len()

Call len() on a list, string, and dictionary; print results.

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7) Operator Polymorphism with +

Use + to add two strings, two lists, and two numbers; print results.

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8) Polymorphism with Inheritance

Create a base class Shape with method area(). Subclass Square and Circle override area(). In a list loop, call area() generically.

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9) Method Overloading (Simple Simulation)

Write a class with a method show(arg=None). If arg is provided, print it; otherwise print default.

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10) Override __str__

Create two classes — both implement __str__. Print instances and show different string formats.

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11) Polymorphism Using Abstract Base Class

(Optional for beginners) Create a base class with empty work() method and subclasses override it. Loop and call work().

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12) Shape Perimeter

Add method perimeter() to Square and Rectangle classes and call generically in a loop.

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13) Polymorphism with Functions

Write function process(item) that prints item info (length if possible, else print item). Test with a string and a number.

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14) Animal Polymorphism with Extra Methods

Create class Bird and class Fish; both have a move() method. In a list call move() for both.

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15) Polymorphism with Lists of Objects

Create several classes with a common info() method. Store objects in a list and call .info() on each.

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16) Read Different Types with Same Function

Write a function print_value(x) that prints whether x is a string, list, or number — call with different types.

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17) Polymorphic Math Operation

Define two classes, each implementing calculate(a, b):

• Class1 returns a + b

• Class2 returns a * b Call .calculate() on both.

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18) Reverse Polymorphism

Write two classes with a method reverse():

• One reverses a list

• One reverses a string Call both using a shared function.

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19) Polymorphism with Default Arguments

Define two classes, both with method greet(name=None) but different default messages. Call with and without arguments.

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20) Polymorphic Sorting

Given a list of objects with a .key() method, sort them using:

sorted(list_of_objects, key=lambda x: x.key())

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🧠 Concepts Practiced

Topic	What You Learn
Method overriding	Different behavior in subclasses
Duck typing	No inheritance needed
Built-in polymorphism	len(), + operator
Generic functions	Work with any object with required method
__str__ polymorphism	Customize printing
Shared interfaces	Common method names across classes

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📌 Example Starter for #1

class Animal:
    def sound(self):
        pass

class Dog(Animal):
    def sound(self):
        print("Woof!")

class Cat(Animal):
    def sound(self):
        print("Meow!")

animals = [Dog(), Cat()]

for a in animals:
    a.sound()

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canvil: 333f6c7d-6876-4f7e-b6ad-1bdb2233f5c1