docs: def page_str(self):
          """
          The RestructuredText documentation page for the enumeration. This is
          the only API member for the class.
          """
          tmpl = '.. _%s:\n\n%s\n\n%s\n\n----\n\n%s'
          components = (
              self._ms_name, self._page_title, self._intro_text,
              self._member_defs
          )
          return tmpl % components