code: def _parse_rd(self, config):
          
          match = RD_RE.search(config)
          if match:
              value = match.group('value')
          else:
              value = match
          return dict(rd=value)
docs: _parse_rd scans the provided configuration block and extracts
          the vrf rd. The return dict is intended to be merged into the response
          dict.
  
          Args:
              config (str): The vrf configuration block from the nodes running
                  configuration
  
          Returns:
              dict: resource dict attribute