input: Write a function to convert a list of books into a dictionary representation. Each book is represented as a list with the elements [title, author, number_pages]. Return a list of dictionaries with each book represented as {'title': title, 'author': author, 'pages': number_pages}.
  assert book_list_to_dict([['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}]
output: def book_list_to_dict(books):
      return [{'title': book[0], 'author': book[1], 'pages': book[2]} for book in books]