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

Posted by Ariadna Rodriguez
Ariadna Rodriguez
6,281 Points

Create a __str__ method for this book class. Return a string with the author and title of the book. Ex: John Green, Pape

I'm confused why it keeps asking me to input John Green and Papertowns

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


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

book_one = Book('John Green', 'PaperTowns')
print(str(book_one)
bookcase.py 
from book import Book


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

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

8 Answers

jlgreenlaw
jlgreenlaw
10,093 Points
jlgreenlaw
jlgreenlaw
10,093 Points

Took me a while to figure this out. Hope this helps!

def __str__(self):
    return f'{self.author}, {self.title}'

book_one = Book("John Green", "Paper Towns")

Brandon Thompson
Brandon Thompson
3,018 Points
Brandon Thompson
Brandon Thompson
3,018 Points

It says I should return the string, not print it. But I noticed that you didn't correct that on this example. Kinda confusing when you used print in your example, and we are being asked to do it differently.

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

    def __str__(self):
        return f'{self.author}, {self.title}'

book_one= Book('John Green', 'PaperTowns')
print(str(book_one))
Nischal Shrestha
Nischal Shrestha
2,027 Points
Nischal Shrestha
Nischal Shrestha
2,027 Points

class Book: def init(self, author, title): self.author = author self.title = title

def __str__(self):
    return "{}, {}".format(self.author,self.title)
Oscar Gomez
Oscar Gomez
6,797 Points
Oscar Gomez
Oscar Gomez
6,797 Points

don't: print (str(book_one)) only state: str(book_one)

Once I cleared this error and added the comma as above it worked!! Also the error message said not to print.

Megan L
Megan L
2,905 Points
Megan L
Megan L
2,905 Points

WORKING SOLUTION

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

    def __str__(self):
        return f'{self.author}, {self.title}'
Daniel Akalu
Daniel Akalu
5,018 Points
Daniel Akalu
Daniel Akalu
5,018 Points

class Book: def init(self, author, title): self.author = author self.title = title def str(self): author = 'John Green' title = 'Paper Towns' return f'{self.author}, {self.ti

ayawovi Badohoun
ayawovi Badohoun
10,334 Points
ayawovi Badohoun
ayawovi Badohoun
10,334 Points

class Book: def init(self, author, title): self.author = author self.title = title def str(self): return f'{self.author}, {self.title}'
book_one = Book('John Green', 'PaperTowns') state: str(book_one)