This document discusses classes in Python. It defines a class as a blueprint for objects, with variables and methods. An example Bike class is provided with name and gear variables. An Employee class is also shown with an id and name variable and a display method using self. The document then discusses classes as abstract data types (ADTs), where the behavior is defined but not the implementation. It provides syntax to create an abstract class in Python. Finally, it introduces data classes in Python 3.7 for storing structured data, with attributes declared using type hints and equality checking using ==.

1. An Example of class, Class as Abstract Data Type, Date Class
By:
P. Gayathri
I M.SC CS
Department of Computer Science
Nadar Saraswathi College of arts and science
Python programming

2. Class:
A class is considered as a blueprint of objects. We can think of the class as a sketch (prototype) of a
house. It contains all the details about the floors, doors, windows, etc. Based on these descriptions we build
the house. House is the object.
Object:
An object is simply a collection of data (variables) and methods (functions). Similarly, a class is a
blueprint for that object.

3. Define Python Class
We use the class keyword to create a class in Python. For example,
class classname :
# class definition

4. Example:
Class bike:
name=“”
gear=0
Bike is the name of the class and name and gear is the
variables for the class.

5. Example
class Employee:
id = 10
name = "Devansh"
def display (self):
print(self.id , self.name)
Here, the self is used as a reference variable, which refers to the current class object.
It is always the first argument in the function definition. However, using self is optional in the function
call.
The self-parameter
The self-parameter refers to the current instance of the class and accesses the class variables.
We can use anything instead of self, but it must be the first parameter of any function which belongs to
the class.

6. Class as Abstract Data Type:
 Abstract Data type (ADT) is a type (or class) for objects whose behavior is
defined by a set of values and a set of operations.
 The definition of ADT only mentions what operations are to be performed but
not how these operations will be implemented.
 It does not specify how data will be organized in memory and what algorithms
will be used for implementing the operations.

7. We can use the following syntax to create an abstract class in Python:
from abc import ABC
class <Abstract_Class_Name>(ABC):
# body of the class

8. Data Class
Data class module is introduced in Python 3.7 as a utility tool to make
structured classes specially for storing data. These classes hold certain
properties and functions to deal specifically with the data and its
representation.
The Data Classes are implemented by using with classes. Attributes are
declared using Type Hints in Python which is essentially, specifying
data type for variables in python.

9. Equality of Data Classes
Since the classes store data, checking two objects if
they have the same data is a very common task that’s
needed with data classes. This is accomplished by using
the == operator.
Below is the code for an equivalent class for storing an
article without a data class decorator.

10. THANK YOU