code: def add_title_translation(self, title, language, source=None):
          
          title_translation = self._sourced_dict(
              source,
              title=title,
              language=language,
          )
  
          self._append_to('title_translations', title_translation)
docs: Add title translation.
  
          :param title: translated title
          :type title: string
  
          :param language: language for the original title
          :type language: string (2 characters ISO639-1)
  
          :param source: source for the given title
          :type source: string