def METHOD_NAME(self):
    from ilastik.workflows.carving.carvingTools import parallel_watershed, agglomerate_labels
    shape = (200,) * 2
    x = numpy.random.rand(*shape).astype("float32")
    over_seg, max_id1 = parallel_watershed(x, max_workers=4, block_shape=[50, 50], halo=[10, 10])
    seg, max_id2 = agglomerate_labels(x, over_seg, max_workers=4, reduce_to=0.8)
    assert not numpy.allclose(seg, 0), "Expect agglomerated labels to not be empty"
    assert (
        max_id2 < max_id1
    ), f"Expect number of labels after {max_id2} to be less than before {max_id1} agglomeration"