Lecture : Creating a class & class attributes

class Product:

    quantity = 200


product1 = Product()

print(product1)

print(product1.quantity)

product2 = Product()
print(product2.quantity)

Lecture : Instance attributes & constructor

class Product:
    quantity = 200

    
    def __init__(self,name,price):
        
        self.name = name
        
        self.price = price


product2 = Product("Phone",500)
print(product2.name)
print(product2.price)

Lecture : Methods

class Product:
    quantity = 200

    def __init__(self,name,price):
        self.name = name
        self.price = price

    def summer_discount(self,discount_percent):
        self.price = self.price - (self.price *discount_percent/100)

product1 = Product("Laptop",500)
print(product1.price)

#let's call the method on object here
product1.summer_discount(10)
print(product1.price)

.

Lecture : Function based v/s OOP based way of writing code

def product_data():
    product_name = input('Enter name of product')
    product_price = input('Enter price of product')
    print(product_name)
    print(product_price)

product_data()

class Product:

    def __init__(self,name,price):
        self.name = name
        self.price = price

    def get_data(self):
        self.name = input('Enter name')
        self.price = input('Enter price')

    def put_data(self):
        print(self.name)
        print(self.price)

product1 = Product("","")
product1.get_data()
product1.put_data()

Lecture : Inheritance

class Product:

    def __init__(self,name,price):
        self.name = name
        self.price = price

    def get_data(self):
        self.name = input('Enter name')
        self.price = input('Enter price')

    def put_data(self):
        print(self.name)
        print(self.price)

class DigitalProduct(Product):

    def __init__(self,link):
        self.link = link

    def get_link(self):
        self.link = input('Enter product link')

    def put_link(self):
        print(self.link)

ebook = DigitalProduct("")
ebook.get_data()
ebook.get_link()
ebook.put_data()
ebook.put_link()

Lecture : Multiple inheritance

class A:
    def method_a(self):
        print('Method of class A')

class B:
    def method_b(self):
        print('Method of class B')

class C(A,B):
    def method_c(self):
        print('Method of class C')

cobject = C()
cobject.method_a()
cobject.method_b()
cobject.method_c()

Lecture 8: Multi-level inheritance

class A:
    def method_a(self):
        print('Method of class A')

class B(A):
    def method_b(self):
        print('Method of class B')

class C(B):
    def method_c(self):
        print('Method of class C')

cobject = C()
cobject.method_a()
cobject.method_b()
cobject.method_c()

Lecture : Polymorphism

print(10+20)
print('Hello'+'world')

# In this case python counts the number of characters in a string
print(len('HelloWorld'))
# In this case python counts the number of items in a list
print(len(['Apple','Mango','Banana']))

Lecture : Method overriding

class Food:
    def type(self):
        print("Food")

class Fruit(Food):
    def type(self):
        print('Fruit')

burger = Food()
print(burger.type())
# this invokes the method in the Food class

apple = Fruit()
print(apple.type())
# The method in the Fruit class overrides the method in the Food class.

.

Lecture : Operator overloading

class Point:
    def __init__(self,x,y):
        self.x = x
        self.y = y

    #To overload the + operator, we use the __add__ method
    # To perform overloading, python provides a special method
    # to overload the + operator we use the magic method __add__

    # we want the plus operator to perform addition of two Points/ two objects
    def __add__(self, other):
        x = self.x + other.x
        y = self.y + other.y
        #once we have the values of x and y we want to return then into a point
        return Point(x,y)

point1 = Point(1,2)
point2 = Point(3,4)
print(point1+point2)

def __str__(self):
        return '({0},{1})'.format(self.x,self.y)

class Point:
    def __init__(self,x,y):
        self.x = x
        self.y = y

   

    
    def __add__(self, other):
        x = self.x + other.x
        y = self.y + other.y
        #once we have the values of x and y we want to return then into a point
        return Point(x,y)

    def __str__(self):
        return '({0},{1})'.format(self.x,self.y)

point1 = Point(1,2)
point2 = Point(3,4)
print(point1+point2)