code: def short_title(self):
          
          if self.title and self.parent is not None and hasattr(self.parent, 'title') and self.parent.title:
              if self.title.startswith(self.parent.title):
                  short = self.title[len(self.parent.title):].strip()
                  match = _punctuation_re.match(short)
                  if match:
                      short = short[match.end():].strip()
                  if short:
                      return short
          return self.title
docs: Generates an abbreviated title by subtracting the parent's title from this instance's title.