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Python Object-Oriented Python Inheritance Super!

Python cannot sort list from overridden inherited method

An exercise step asks "Sorted inventories should be just that: sorted. Right now, we just add an item onto the slots list whenever our add_item method is called. Use the list.sort() method to make sure the slots list gets sorted after an item is added. Only do this in the SortedInventory class." I have added the sort method to the list but the system keeps saying the items are not sorted. I have tried the code in a external editor and the list is sorted any ideas?

inventory.py
class Inventory:
    def __init__(self):
        self.slots = []

    def add_item(self, item):
        self.slots.append(item)

class SortedInventory(Inventory):
    def add_item(self, item):
        super().add_item(item)
        self.slots.append(item)
        self.slots.sort()

2 Answers

You are adding each item two times to the list. One via the super().add_item(item) and another via self.slots.append(item) which results in all items being duplicated. You should get rid of the latter. Even though your list is sorted, the contents of the list are not what the code challenge is expecting.

Thanks Pedro much appreciated, helps understand whats going on a little better. Once again thank you.