Attributes and Methods

• Attributes are variables that belong to an object or class.
• There are two important types:

Instance Attribute

• Different objects can have different values.

student1 = Student("Punitha", 22)
student2 = Student("Anu", 21)

print(student1.name)
print(student2.name)

Output:

Vijay
Anu

Class Attribute

• A class attribute is shared by objects.

class Student:
    college = "ABC College"

student1 = Student()
student2 = Student()

print(student1.college)
print(student2.college)

Output:
ABC College
ABC College


Methods

• A method is a function defined inside a class.

class Student:
    def study(self):
        print("Student is studying")

student1 = Student()

student1.study()

Output:
Student is studying

There are three commonly discussed method types:

• Instance Method
• Class Method
• Static Method

Instance Method

• An instance method works with an object.

class Student:

    def display(self):
        print("Student details")

student1 = Student()
student1.display()

Class Method

• We use @classmethod.

class Student:

    college = "ABC College"

    @classmethod
    def display_college(cls):
        print(cls.college)

Student.display_college()

• Here cls refers to the class.

Static Method

• A static method does not require self or cls.

class Student:

    @staticmethod
    def message():
        print("Welcome to Python OOP")

Student.message()