classmethod.py

class Store:
    def __init__(self, name):
        self.name = name
        self.items = []

    def add_item(self, name, price):
        self.items.append({
            'name': name,
            'price': price
        })

    def stock_price(self):
        total = 0
        for item in self.items:
            total += item['price']
        return total

    @classmethod
    def franchise(cls, store):
        cls = store
        return "{} - franchise".format(cls.name)
        # Return another store, with the same name as the argument's name, plus " - franchise"

    @staticmethod
    def store_details(store):
        #pass
        return "{}, total stock price: {}".format(store.name, store.stock_price())
        # Return a string representing the argument
        # It should be in the format 'NAME, total stock price: TOTAL'

Hey!

In the franchise method, you have two arguments: cls, a reference to the class (i.e. cls and Store are the same thing); and store, a Store object that has a name and potentially a list of items.

However, in line 20 you assign cls = store, which means cls is no longer a reference to the class.

The method is meant to "Return another store", which means it must return a Store object. In line 21, you return a string.

In order to return a Store object with the correct name, you should change line 21 to this:

return Store("{} - franchise".format(cls.name))

If you delete line 20, then you can use cls instead of Store (and you'll have to access store.name instead of cls.name):

return cls("{} - franchise".format(store.name))

Thanks for the detailed explanation, @jslvtr!