Classes and Objects in Python – Key Differences, Syntax, Examples, & More

Python classes and objects were introduced by Ole-Johan Dahl and Kristen Nygaard at the Norwegian Computing Center in the early 1960s. Classes are templates for creating objects, and they provide all of the properties that define an object’s behavior. 

Objects are instances of a class that contains their own data attributes and methods to manipulate those attributes. In Python, classes and objects are basic concepts in object-oriented programming (OOP). They enable you to build reusable frameworks and set performances for various types of objects.

What are Classes and Objects in Python?

A class in Python is a collection of related data and functions. Classes are used to create objects, which can be used to store and manipulate data. Creating a class in Python is done using the keyword ‘class’ followed by the name of the desired class. Inside this definition, one can define various attributes or assign values to them and specify any methods that should be available for manipulation with this object type. 

Objects in Python are instances of a class that contains their own data attributes and methods. Objects can be created by calling the class name as if it were a function, passing any necessary arguments to initialize the object’s state. Each object will have its own unique set of attributes that define its behavior, and these can be accessed or changed using the appropriate methods associated with the object type.

To learn more about classes and objects in Python, you can pursue a Python course.

Example of Class and Object in Python

Building an entity in Python includes initializing a class to generate a new case of that class. This method is also known as object instantiation.

# Python3 program to demonstrate instantiating a class
class Animal:
    # A simple class attribute
    species = "mammal"
    sound = "roar"
 
    # A sample method
    def make_sound(self):
        print("I'm a", self.species)
        print("I", self.sound)
 
 
# Driver code
# Object instantiation
Simba = Animal()
 
# Accessing class attributes and method through objects
print(Simba.species)
Simba.make_sound()

The above Python code illustrates building a class called “Animal” with a class property “species” defined as “mammal” and a method “make_sound” that prints the species and a sound.

In the program, an object “Simba” is created employing the “Animal” class. The program then retrieves the class characteristics “species” and calls the “make_sound” function on the “Simba” object.

The output of the program is:

mammal

I’m a mammal

I roar

It primarily prints the value of the “species” properties: “mammal”. Then, it calls the “make_sound” technique, which prints “I’m a mammal” and “I roar”.

Creating  Classes and Objects in Python

Generating classes and objects in Python requires describing a class to encapsulate data and capabilities, and then making examples of that class.

Following are the steps to create a class and objects in Python:

• Declare the class: Utilize the class keyword and assign a title. Define properties and functions within the class to specify its performance.

• Construct objects: Instantiate objects by executing the class name by parenthesis. Define the object as an entity for future utilization.

• Access properties and functions: Use dot notation to access attributes and call methods on the objects (object_name.attribute_name or object_name.method_name()).

Here’s a simple example:

# Define the class
class Animal:
    # Class attribute
    species = "Dog"
    
    # Method
    def make_sound(self):
        print("Woof!")
        
# Instantiate objects
animal1 = Animal()
animal2 = Animal()

# Access attributes and methods
print(animal1.species)  # Output: Dog
animal1.make_sound()    # Output: Woof!

In this revised version, the class is now named “Animal” with the class properties “species” assigned to “Dog”. The function is labeled “make_sound” and it prints “Woof!”. The objects created are called “animal1” and “animal2”. When fetching properties and executing methods, you’ll get the modified outputs.

Difference between Class and Objects in Python

Let’s have a look at the difference between class and object in Python for a better understanding:

Class	Object
Class is applied as a framework for specifying and creating the objects.	An object is an experience of a class.
No allocation of memory space happens in Classes during their constructions.	In objects, reserve memory space is reserved when constructed.
The class has to be declared first and only once.	An object is constructed multiple times as per the condition.
A class is incapable of being modified as they are not usable in the memory.	Objects can be changed.
A class is a virtual entity.	An object is a real entity.
It is specified using the class keyword	It is built with a class name in C++ and with the new keywords in Java.

Syntax for Class and Object in Python

In Python, you can identify a class by utilizing the class keyword. The class is a blueprint for making objects, which are examples of the class. Following is the basic syntax for identifying a class and creating objects:

class ClassName:
    # Class variables (shared by all instances of the class)
    class_variable = value

    # Constructor (initialize instance variables)
    def __init__(self, parameter1, parameter2, ...):
        self.instance_variable1 = parameter1
        self.instance_variable2 = parameter2
        ...

    # Instance methods (perform actions on the instance)
    def method1(self, parameter1, parameter2, ...):
        # method body

    def method2(self, parameter1, parameter2, ...):
        # method body

# Creating objects
object1 = ClassName(arg1, arg2, ...)
object2 = ClassName(arg1, arg2, ...)

Conclusion

Classes and Objects in Python offer an easy way to arrange code and give improved data storage capabilities. Programmers use them to build separate documents or modules, leading to a well-structured and managed codebase.