docs: def update_persistent_boot(self, devices=[]):
          """Changes the persistent boot device order for the host
  
          :param devices: ordered list of boot devices
          :raises: IloError, on an error from iLO.
          :raises: IloInvalidInputError, if the given input is not valid.
          """
          sushy_system = self._get_sushy_system(PROLIANT_SYSTEM_ID)
          # Check if the input is valid
          for item in devices:
              if item.upper() not in DEVICE_COMMON_TO_REDFISH:
                  msg = (self._('Invalid input "%(device)s". Valid devices: '
                                'NETWORK, HDD, ISCSI or CDROM.') %
                         {'device': item})
                  raise exception.IloInvalidInputError(msg)
  
          try:
              sushy_system.update_persistent_boot(
                  devices, persistent=True)
          except sushy.exceptions.SushyError as e:
              msg = (self._('The Redfish controller failed to update '
                            'persistent boot device %(devices)s.'
                            'Error: %(error)s') %
                     {'devices': devices, 'error': str(e)})
              LOG.debug(msg)
              raise exception.IloError(msg)