def METHOD_NAME(self):
    ctx = get_tiles_ctx()
    with self.assertRaises(ApiError.BadRequest) as cm:
        compute_ml_dataset_tile(
            ctx, 'demo', 'rgb', 'CRS84', '0', '0', '0', {}
        )
    self.assertEqual("HTTP status 400:"
                     " No variable in dataset 'demo'"
                     " specified for RGB component R",
                     f'{cm.exception}')