add a Book.all method to create objects of all books in database
add a Parton.all_partons method to create objects of all patrons in database
add a Authors.all_authors method to create objects of all authors in database
move the Author.all_authors method to Author class and re-added the Book.all_books method that was accidently deleted
add Book.update_title method to Book to rename the title of a book in the database
add a Book.new_book method that deletes the book from the database
add Book.list_titles method to list out all the book titles in the database
add Author.list_authors method to list out all the authors names in the database
add Author.authors_books method to add multiple authors to a single book in the join table within the database
update Book.new_book to add the book_id to the copies table in the database
add a Book.new_copies method to increase the number of copies of a specific book in the copies table