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Classes and Objects in Python

 


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Classes and Objects in Python

In Python, a class is a blueprint for creating objects. An object is an instance of a class. Classes allow you to logically group data and functions in a way that is easy to manage and reuse.

1. Defining a Class

To define a class in Python, you use the class keyword followed by the class name and a colon. Inside the class, you can define attributes and methods.

Example:


# Define a class
class Person:
    # Class attribute
    species = 'Human'

    # Class method
    def greet(self):
        return 'Hello, I am a person.'

# Create an object of the class
person1 = Person()

# Access class attribute
print(person1.species)  # Output: Human

# Call class method
print(person1.greet())  # Output: Hello, I am a person.

2. Creating Objects

To create an object of a class, you simply call the class name followed by parentheses. This invokes the class's constructor, which initializes the object.

Example:


# Define a class
class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = age

# Create an object of the class
person1 = Person('Alice', 30)

# Access object attributes
print(person1.name)  # Output: Alice
print(person1.age)   # Output: 30

3. Object Attributes and Methods

Objects of a class can have attributes and methods. Attributes are data members that store information about the object. Methods are functions that belong to the object and can perform actions or manipulate the object's data.

Example:


# Define a class
class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = age

    def introduce(self):
        return "Hello, my name is {} and I am {} years old.".format(self.name, self.age)

# Create an object of the class
person1 = Person('Alice', 30)

# Call object method
print(person1.introduce())  # Output: Hello, my name is Alice and I am 30 years old.

Classes and objects are fundamental concepts in object-oriented programming and are widely used in Python for organizing and structuring code.

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