def METHOD_NAME(self):
    chooser = RaidChooser()
    chooser.supported_raids = {"mdraid": [RAID0, RAID1, RAID5, Linear]}
    chooser.update("mdraid", 2)
    # raid5 not supported for 2 devices
    with self.assertRaises(ValueError):
        chooser.selected_level = RAID5
    chooser.selected_level = RAID1
    self.assertEqual(chooser.selected_level, RAID1)