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

Posted by jack twist
.a{fill-rule:evenodd;}techdegree
jack twist
Full Stack JavaScript Techdegree Student 18,575 Points

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 68,454 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,454 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!!!

jack twist
.a{fill-rule:evenodd;}techdegree
jack twist
Full Stack JavaScript Techdegree Student 18,575 Points

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 68,454 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,454 Points

Sorry two errors left:

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