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Python Object-Oriented Python Inheritance Super!

Keenan Smith
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Keenan Smith
Python Development Techdegree Student 5,487 Points
Posted by Keenan Smith
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Keenan Smith
Python Development Techdegree Student 5,487 Points

Stuck on SortedInventory class

looking in my notes I thought this is what it is asking us to do. I keep getting a bummer error though. What am I doing wrong?

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

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

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

1 Answer

Steven Parker
Steven Parker
231,268 Points
Steven Parker
Steven Parker
231,268 Points

The instructions ask you to "override the add_item method.", but this code is overriding "__init__" instead.

Also, you won't need to call "append" yourself, since it will be done by the "super" call.

Keenan Smith
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.a{fill-rule:evenodd;}techdegree
Keenan Smith
Python Development Techdegree Student 5,487 Points
Keenan Smith
.a{fill-rule:evenodd;}techdegree
Keenan Smith
Python Development Techdegree Student 5,487 Points

Ok, so I think now I understand what it was asking for when it said override. Thank you. now after fixing that and eliminating the append code, im getting an error that says: "Bummer: You need to override add_item inside of SortedInventory. For now, just have it call super()"

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

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

class SortedInventory(Inventory):
    def add_items(self, item):
        super().add_item(self, item)

Is it not overriding even though I'm creating the method add_items?

Steven Parker
Steven Parker
231,268 Points
Steven Parker
Steven Parker
231,268 Points

You need to "override the add_item method.", but this code is defining "add_items" (plural) instead.

And when you call a method, you don't need to pass "self" explicitly. The system adds that for you.

Keenan Smith
seal-mask
.a{fill-rule:evenodd;}techdegree
Keenan Smith
Python Development Techdegree Student 5,487 Points
Keenan Smith
.a{fill-rule:evenodd;}techdegree
Keenan Smith
Python Development Techdegree Student 5,487 Points

That worked out. had that not been a challenge could we just have sorted the list within the Inventory class? Or is it better to have a new class do it?

Steven Parker
Steven Parker
231,268 Points
Steven Parker
Steven Parker
231,268 Points

You could have added sorting to the original class, but maybe there would be a reason to retain the original order of creation (it's not clear from just the code).