5 Levels of Writing Python Classes

 

Level 1: Basic Class Creation and Instantiation

# Defining a basic class

class Dog:

    def __init__(self, name, age):

        self.name = name

        self.age = age

# Creating an instance

my_dog = Dog('Buddy', 3)

# Accessing attributes

print(my_dog.name)  

print(my_dog.age)   

#clcoding.com

Buddy

3

Level 2: Methods and Instance Variables

# Defining a class with methods

class Dog:

    def __init__(self, name, age):

        self.name = name

        self.age = age

    def bark(self):

        print(f"{self.name} says woof!")

# Creating an instance and calling a method

my_dog = Dog('Buddy', 3)

my_dog.bark()  

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Buddy says woof!

Level 3: Class Variables and Class Methods

# Defining a class with class variables and methods

class Dog:

    species = 'Canis familiaris'  # Class variable

    def __init__(self, name, age):

        self.name = name

        self.age = age

    def bark(self):

        print(f"{self.name} says woof!")

    @classmethod

    def get_species(cls):

        return cls.species

# Accessing class variables and methods

print(Dog.species)  

print(Dog.get_species())  

#clcoding.com

Canis familiaris

Canis familiaris

Level 4: Inheritance and Method Overriding

# Base class and derived classes

class Animal:

    def __init__(self, name):

        self.name = name

    def speak(self):

        raise NotImplementedError("Subclasses must implement this method")

class Dog(Animal):

    def speak(self):

        return f"{self.name} says woof!"

class Cat(Animal):

    def speak(self):

        return f"{self.name} says meow!"

# Instances of derived classes

my_dog = Dog('Buddy')

my_cat = Cat('Whiskers')

# Calling overridden methods

print(my_dog.speak())  

print(my_cat.speak())  

#clcoding.com

Buddy says woof!

Whiskers says meow!

Level 5: Advanced Features (Polymorphism, Abstract Base Classes, Mixins)

from abc import ABC, abstractmethod

# Abstract base class

class Animal(ABC):

    @abstractmethod

    def speak(self):

        pass

# Derived classes implementing the abstract method

class Dog(Animal):

    def __init__(self, name):

        self.name = name

    def speak(self):

        return f"{self.name} says woof!"

class Cat(Animal):

    def __init__(self, name):

        self.name = name

    def speak(self):

        return f"{self.name} says meow!"

# Polymorphism in action

def animal_speak(animal):

    print(animal.speak())

# Creating instances

my_dog = Dog('Buddy')

my_cat = Cat('Whiskers')

# Using polymorphism

animal_speak(my_dog)  

animal_speak(my_cat)  

Buddy says woof!

Whiskers says meow!