How to use the @times-components/fixture-generator.MockUser function in @times-components/fixture-generator

beforeEach(() => {
      sundayTimesArticleWithThreeRelatedArticles = new MockArticle()
        .sundayTimes()
        .setRelatedArticles(relatedArticleCount)
        .setTemplate(template)
        .get();

      userWithBookmarks = new MockUser().setBookmarksTotal(3);
    });

beforeEach(() => {
      sundayTimesArticleWithThreeRelatedArticles = new MockArticle()
        .sundayTimes()
        .setRelatedArticles(relatedArticleCount)
        .setTemplate(template)
        .get();

      userWithBookmarks = new MockUser().setBookmarksTotal(3);
    });