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

def __str__(self):: return f`{self.author} {self.title}` what's wrong with the syntax?

I followed the syntax from the video exactly, why do i get invalid syntax?

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

    def __str__(self)::
            return f`{self.author} {self.title}`
bookcase.py
from book import Book


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

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

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 67,778 Points

Hey jack twist, it looks like your quotation marks are “backticks” and not single quote marks. You have ` when you need ‘

Post back if you need more help. Good luck!!!

Hey Chris, thanks for your answer! I changed the my code to

 <--    def __str__(self):
            return f'{self.author} {self.title}'   -->

but it still doesn't pass:

----------------------------------------------------------------------
Traceback (most recent call last):
  File "", line 64, in test_results
AssertionError: 'John Green Paper Towns' != 'John Green, Paper Towns'
- John Green Paper Towns
+ John Green, Paper Towns
?           +
 : Hmm...when I input John Green, Paper Towns
Chris Freeman
Chris Freeman
Treehouse Moderator 67,778 Points

Sorry two errors left:

  • colon should be single : not doubled ::
  • a comma is missing from the formatted string after the author name