class LibraryBook:
    def __init__(self, title, author, isbn, year_published):
        self.title = title
        self.author = author
        self.isbn = isbn
        self.year_published = year_published
        self.available = True

    def borrow(self):
        if self.available:
            self.available = False
            print(f"You have borrowed '{self.title}' by {self.author}.")
        else:
            print(f"Sorry, '{self.title}' is currently not available.")

    def return_book(self):
        if not self.available:
            self.available = True
            print(f"You have returned '{self.title}'. Thank you!")
        else:
            print(f"'{self.title}' was not borrowed.")  

    def detail(self):
          print(f"Title: {self.title}")
          print(f"Author: {self.author}")
          print(f"ISBN: {self.isbn}")
          print(f"Year Published: {self.year_published}")
          print(f"Available: {'Yes' if self.available else 'No'}")    

    book1 = LibraryBook("To Kill a Mockingbird", "Harper Lee", "978-0-06-112008-4", 1960)    # type: ignore
    book2 = LibraryBook("1984", "George Orwell", "978-0-452-28423-4", 1949)  # type: ignore
    book3 = LibraryBook("Pride and Prejudice", "Jane Austen", "978-0-19-953556-9", 1813)     # type: ignore
    #book1
    detail = book1.detail()
    borrow = book1.borrow()
    detail = book1.detail()
    return_book = book1.return_book()
    detail = book1.detail()

    #book2
    detail = book2.detail()
    borrow = book2.borrow()
    detail = book2.detail()
    return_book = book2.return_book()
    detail = book2.detail()

    #book3
    detail = book3.detail() 
    borrow = book3.borrow()
    detail = book3.detail()
    return_book = book3.return_book()
    detail = book3.detail()

    #newattribute
    def availability(self):
        if self.available:
            print("True")
        elif self.borrow:
            print("False")
        if self.return_book:
            print("True")
        if self.already_borrowed:
            print("This book is already borrowed.")