docs: def _get_iscsi_settings_resource(self, data):
          """Get the iscsi settings resoure.
  
          :param data: Existing iscsi settings of the server.
          :returns: headers, iscsi_settings url and
                   iscsi settings as a dictionary.
          :raises: IloCommandNotSupportedError, if resource is not found.
          :raises: IloError, on an error from iLO.
          """
          try:
              iscsi_settings_uri = data['links']['Settings']['href']
          except KeyError:
              msg = ('iscsi settings resource not found.')
              raise exception.IloCommandNotSupportedError(msg)
  
          status, headers, iscsi_settings = self._rest_get(iscsi_settings_uri)
  
          if status != 200:
              msg = self._get_extended_error(iscsi_settings)
              raise exception.IloError(msg)
  
          return headers, iscsi_settings_uri, iscsi_settings