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

sa,m cohn
sa,m cohn
Courses Plus Student 2,010 Points

Hello, I keep receiving a NameError when trying to complete a task even though I've clearly defined the class.

I am completing a task where I create a eq method to check if the author and title of a book are the same and then return true if they are and false if they aren't. When I run the code, I keep getting a NameError saying I haven't defined Book, even though I did at the top of my code with a class. Can I get some help?

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
from book import Book

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

    def add_books(self, book):

1 Answer

Steven Parker
Steven Parker
228,026 Points

Oddly, this seems to work fine in the workspace.

But in general, you want to avoid referencing a class by name from inside its own code. So instead of Book, you can compare to self.__class__ instead.

Also, the "isinstance" check is a nice touch but isn't necessary for the challenge.