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

Tim Good
Tim Good
6,021 Points

Why does it keep giving me this error; "Book is not defined"

I've tried everything on this task and it keeps giving me that same error.

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):
        if isinstance(other, Book):
            return self.author == other.author and self.title == other.title
        return False
bookcase.py
from book import Book

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

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

# Example usage
personal = Book("John Green", "Paper Towns")
print(personal)  # Output: John Green, Paper Towns

bookcase = BookCase()
bookcase.add_books(personal)
print(bookcase.books)  # Output: [John Green, Paper Towns]

1 Answer

Travis Alstrand
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Travis Alstrand
Data Analysis Techdegree Graduate 49,444 Points

What you have within the conditional works perfect for me on its own for this challenge. As far as I remember, using isinstance is valid in this scenario so it must be how the backend of the challenge is running or what it's specifically looking for as an answer.

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