classmethod.py

import csv
#Class attributes will belong to the class itself
class Item:
    pay_rate = 0.8 
    all = []
    def __init__(self, name: str, price: float, quantity=0):
        assert price >= 0, f"Price {price} is not greater than or equal to zero "
        assert quantity >= 0, f"Quantity {quantity} is not greater than or equal to zero "
        
        self.name = name
        self.price = price
        self.quantity = quantity

        # Actions to execut
        Item.all.append(self)

    def calculate_total_price(self):
        return self.price * self.quantity

    def apply_discount(self):
        self.price = self.price * self.pay_rate

    @classmethod
    def instantiate_from_csv(cls):  #Method to convert to class method
        with open('items.csv', 'r') as f:
            reader = csv.DictReader(f)
            items = list(reader)

        for item in items:
           Item(
              name=item.get('name'), 
              price=float(item.get('price')), 
              quantity=int(item.get('quantity')), 
           )
    # Representing your objects in your console
    def __repr__(self):
        return f"Item('{self.name}',{self.price},{self.quantity})"

Item.instantiate_from_csv()
print(Item.all)