def test_get_related_objects_create_api(self):
        """
        Must generate Book related data when creates a Book object for API calls.
        New author must be returned if it's name not present in the Author model.
        """
        test_data = {'author': 'trueAuthorNew', 'category': 'category2', 'language': 'Russian'}
        test_data_new_author = {'author': 'NEW AUTHOR', 'category': 'category1', 'language': 'English'}

        self.assertEqual(
            Book.get_related_objects_create_api(self.the_user1, test_data),
            BookRelatedData(self.author2, self.category2, self.language_ru, None)
        )
        self.assertEqual(Author.objects.all().count(), 5)

        self.assertEqual(
            Book.get_related_objects_create_api(self.the_user1, test_data_new_author),
            BookRelatedData(Author.objects.get(author_name='NEW AUTHOR'), self.category1, self.language_en, None)
        )
        self.assertEqual(Author.objects.all().count(), 6)