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Python Basic Object-Oriented Python Emulating Built-ins Emulating Built-ins

Jorge Grajeda
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.a{fill-rule:evenodd;}techdegree
Jorge Grajeda
Python Development Techdegree Student 4,983 Points

What does it mean "Make sure you have a `__iter__` method in your class" ?

book.py
class Book:
    def __init__(self, author, title):
        self.author = author
        self.title = title

    def __str__(self):
        return f'{self.author}, {self.title}'

    def __eq__(self, other):
        return self.author == other.author and self.title == other.title

    def __iter__(self):
        yield from self.book
bookcase.py
from book import Book


class BookCase:
    def __init__(self):
       self.books = []

    def add_books(self, book):
        self.books.append(book)

1 Answer

Jeff Muday
MOD
Jeff Muday
Treehouse Moderator 28,715 Points

You're really close to solving!

If you switch "tabs" and add the __iter__() method there. You will solve the Challenge.

Good luck with your Python journey!

book.py

class Book:
    def __init__(self, author, title):
        self.author = author
        self.title = title

    def __str__(self):
        return f"{self.author}, {self.title}"

    def __eq__(self, other):
        return self.author == other.author and \
            self.title == other.title

bookcase.py

from book import Book

class BookCase:
    def __init__(self):
       self.books = []

    def add_books(self, book):
        self.books.append(book)

    def __iter__(self):
        yield from self.books