input: Write a function to create a list of dictionaries where each dictionary represents a book. Each book should include the title, author, and number of pages. If the input is an empty list, the function should return an empty list.
  assert book_dictionary([['The Hobbit', 'J.R.R. Tolkien', 295], ['The Catcher in the Rye', 'J.D. Salinger', 223]])==[
    {'title': 'The Hobbit', 'author': 'J.R.R. Tolkien', 'pages': 295},
    {'title': 'The Catcher in the Rye', 'author': 'J.D. Salinger', 'pages': 223},
  ]
  assert book_dictionary([])==[]
output: def book_dictionary(books):
      return [{'title': book[0], 'author': book[1], 'pages': book[2]} for book in books]