new_contents: import unittest
  
  from clippings.parser import Document
  
  
  class DocumentTest(unittest.TestCase):
  
      def test_create_document(self):
          title = 'Haunted'
          authors = ['Chuck Palahniuk']
          document = Document(title, authors)
  
          self.assertEqual(title, document.title)
          self.assertEqual(authors, document.authors)
  
      def test_parse_document_with_single_author(self):
          document_line = '1984 (George Orwell)'
          document = Document.parse(document_line)
  
          expected_authors = ['George Orwell']
          self.assertEqual(expected_authors, document.authors)
  
          expected_title = '1984'
          self.assertEqual(expected_title, document.title)
  
      def test_parse_document_with_multiple_authors(self):
          document_line = 'Java Concurrency in Practice (Joshua Bloch;Brian Goetz)'
          document = Document.parse(document_line)
  
          expected_authors = [
              'Joshua Bloch',
              'Brian Goetz',
          ]
          self.assertEqual(expected_authors, document.authors)
  
          expected_title = 'Java Concurrency in Practice'
          self.assertEqual(expected_title, document.title)
  
      def test_document_to_string(self):
          title = 'Also sprach Zarathustra'
          authors = ['Friedrich Nietzsche']
          document = Document(title, authors)
  
          expected_string = 'Also sprach Zarathustra (Friedrich Nietzsche)'
          self.assertEqual(expected_string, str(document))
  
      def test_document_to_dict(self):
          title = 'À la recherche du temps perdu'
          authors = ['Marcel Proust']
          document = Document(title, authors)
  
          expected_dict = {
              'title': title,
              'authors': authors
          }
          self.assertEqual(expected_dict, document.to_dict())
  
subject: Add unit tests for the Document class