def extract_books
      booklist = []
      if @doc.count != 0
        @doc.each do |book_data|
          book = {}
          book['title'] = book_data['titleMain']
          book['book_url'] = BOOK_URL + book_data['prodId']
          book['crt_time'] = book_data['crtTime'].split(' ')[0]
          booklist << book
        end
      end
      booklist
    end
def extract_books
      booklist = []
      if @doc.count != 0
        @doc.each do |book_data|
          book = {}
          book['title'] = book_data['titleMain']
          book['book_url'] = BOOK_URL + book_data['prodId']
          book['crt_time'] = book_data['crtTime'].split(' ')[0]
          booklist << book
        end
      end
      booklist
    end
Return the books in the format specified in spec.