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Python Object-Oriented Python Inheritance Super!

Jorge Grajeda
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Jorge Grajeda
Python Development Techdegree Graduate 8,186 Points
Posted by Jorge Grajeda
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Jorge Grajeda
Python Development Techdegree Graduate 8,186 Points

Inventory.py

Could somebody please help me out for the last part of this challenge?

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)
        def list.sort():
            self.sort()

2 Answers

jb30
jb30
44,806 Points
jb30
jb30
44,806 Points

Instead of super()add_item(item), you could do super().add_item(item).

You don't need to define list.sort(). It's a built in method. You can pass the method your list as an argument, such as list.sort(your_list), and your list will be sorted.

jb30
jb30
44,806 Points

To call a method from within a class, you usually use the form self.add_item(item). When you want to run the superclass's implementation of the method, you can replace self with super(). You will still need to include the . to call the method.

If you have a list such as

some_list = [2, 1, 3]
print(some_list) # prints [2, 1, 3]
some_list.sort()
print(some_list) # prints [1, 2, 3]

Calling sort() directly on the list some_list is equivalent to using list.sort(some_list), and the list is sorted in place, meaning that sort() modifies whatever list you use with it. It's a built-in method of lists, meaning that all lists in python are able to be sorted in this way without needing additional code.

The class Inventory has the list slots, which you can access from within its subclass SortedInventory as self.slots. To sort the list self.slots, you can use self.slots.sort() or list.sort(self.slots).