Object Oriented Programming System (OOPs)
=========================================
-> High level programming languages can be defined with three types of paradigms:
	1) Functional programming approach ==> C, C++, Python etc.
	2) Object Based programming approach ==> VB, VB Script
	3) Object Oriented programming approach ==> C++, Python, Java etc.

def function():
	function body

function()

Object Oriented Programming System:
	concepts:
		class, object, methods, constructor, Destructor etc.
	principles:
		Encapsulation, Inheritance, Polymorphism, Abstraction
==========================================================
Python OOPs:
============
	Class, object, Methods
	Types of variables
	Types of Methods
	Constructor
	Destructor
	Garbage Collection
	Encapsulation
	Polymorphism
	Inheritance
	Abstraction
	Modules
	Packages

Class, Object and Methods
==========================
class:
======
-> Logical element
-> Class is a user-defined/Reference based datatype
Ex: Bank{
	accountNumber;
	balance;
	checkBalance():
}

ecommerce{
	productid;
	productCost;
	paymentGateway():
}
-> class is a collection of attributes (which can hold/store data) and/or methods.
attribute ==> data reference/variable
method ==> named block
-> To define the class in the python:
	we can use "class" keyword.
Syntax:
	class ClassName:
		attributes
		methods
-> While the creation of the class, no memory can be created by PVM.

Function Vs Method:
==================
Function can always write/define outside the class only.
Method can always write/define within the class.

Note:
=====
Java does not support functions.

Object:
=======
-> Physical element
-> Acts as an instance/reference of the class.
-> When we need to access anything from the class, we need the object.
-> The memory can be created for the object at the time of creation/definition. Whereas for the class the memory can be reserved at the time of object creation only.
-> Syntax for the object creation:
	object-name/identifier = ClassName() 

Why we need OOPs concepts?
==========================
-> to achieve:
	Module programming
	Reusability
	Security
	Scalability

# class with attributes
class MyClass:
    # attribute in the compile-time
    a = 101
    # attribute in the run-time
    b = input("Enter some value:")
    
# object creation
mc = MyClass()
print("Static variable = ",mc.a)
print("Dynamic Variable = ",mc.b)
===========================================
Why Methods?
============
Methods can define in the class
to define the attributes
and also to access the attributes.

# class with methods
# methods to access the attributes

class MyClass:
    # instance variables
    a = 101
    b = 121
    c = 131
    
    # method definition
    def displayData(self):
        print("a = ",self.a)
        print("b = ",self.b)
        print("c = ",self.c)

mc = MyClass()
mc.displayData()

=============================================
# class with methods
# methods to access the attributes

class MyClass:
    # instance variables
    def definingData(self):
        self.a = 121
        self.b = 101
        self.c = 131
    
    # method definition
    def displayData(self):
        print("a = ",self.a)
        print("b = ",self.b)
        print("c = ",self.c)

mc = MyClass()
mc.definingData()
mc.displayData()