code: def write_parent (self, url_data):
          
          self.write(self.part('parenturl') + self.spaces("parenturl"))
          txt = url_data.parent_url
          if url_data.line > 0:
              txt += _(", line %d") % url_data.line
          if url_data.column > 0:
              txt += _(", col %d") % url_data.column
          if url_data.page > 0:
              txt += _(", page %d") % url_data.page
          self.writeln(txt, color=self.colorparent)
docs: Write url_data.parent_url.