def METHOD_NAME(self):
    backbone = BackboneMixin()
    backbone.stage_names = ["a", "b", "c"]
    backbone._out_features = ["a", "c"]
    backbone._out_indices = [0, 2]
    # Check that the output features and indices are set correctly
    self.assertEqual(backbone.out_features, ["a", "c"])
    self.assertEqual(backbone.out_indices, [0, 2])
    # Check out features and indices are updated correctly
    backbone.out_features = ["a", "b"]
    self.assertEqual(backbone.out_features, ["a", "b"])
    self.assertEqual(backbone.out_indices, [0, 1])
    backbone.out_indices = [-3, -1]
    self.assertEqual(backbone.out_features, ["a", "c"])
    self.assertEqual(backbone.out_indices, [-3, -1])