docs: def val(self):
          """
          The underline type corresponding to the ``w:val`` attribute value.
          """
          val = self.get(qn('w:val'))
          underline = WD_UNDERLINE.from_xml(val)
          if underline == WD_UNDERLINE.SINGLE:
              return True
          if underline == WD_UNDERLINE.NONE:
              return False
          return underline