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

Omonike Akinfe
Omonike Akinfe
2,999 Points

I'm getting Assertion Error: False is not true: Make sure you have __iter_ method in your class. What am I doing wrong ?

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

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

    def __iter__ (self):
        yield from self.books

    def add_book(self, book):
        self.books.append(Book)

book = Book('John Green', 'Paper Town')

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

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

        def __iter__ (self):
            yield from self.books

        def add_book(self, book):
            self.books.append(Book)

book = Book('John Green', 'Paper Town')
bookcase.py
from book import Book


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

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

1 Answer

Steven Parker
Steven Parker
216,891 Points

The code for "Bookcase" should exist only within bookcase.py, don't duplicate it in book.py.

Also, there should be no space between "__iter__" and the parenthesis