code: def get_slug(self, language_code, lang_name):
          
          title = self.get_title(language_code, lang_name)
          assert title != ""
  
          title = str(title)  # e.g.: evaluate a lazy translation
  
          slug = slugify(title)
          assert slug != "", "Title %r results in empty slug!" % title
          return slug
docs: Notes:
              - slug must be unique!
              - slug is used to check if page already exists!
          :return: 'slug' string for cms.api.create_page()