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Python Object-Oriented Python Advanced Objects Constructicons

Tom Watson
Tom Watson
9,987 Points
Posted by Tom Watson
Tom Watson
9,987 Points

Why use __init__ on Bookcase()?

Why do we need to use __init__ on the Bookcase() class? All I see that is happening here is we are assigning the book attribute to self, but I can't see where this is used? Is it at cls(books)?

I've tried to run this code without defining __init__, and obviously it doesn't work, i'm just trying to understand why!

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,441 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

The line:

    self.books = books

is needed to create the attribute books on the Bookshelf class instance. It is in this attribute that the list of Book instances are stored. Without this attribute the Bookshelf instance would contain nothing and the Bookshelf __init__ method that initializes the Bookshelf instance would not do anything with the list of books passed in.

Please post back if you need more help. Good luck!