class_book.py

class Book:
    title = None
    author = None
    year = None

    def __init__(self, author, title, year):
        self.author = author
        self.title = title
        self.year = year
    
    # Equality check implementation
    def __eq__(self, other):
        return self.author == other.author and \
               self.title == other.title and \
               self.year == other.year

    # Hash implementation
    def __hash__(self):
        return hash(('author', self.author,
                     'title', self.title,
                     'year', self.year))

    def __str__(self):
        return f"{self.title} by {self.author} in {self.year}"