def scrutinize_contour(points):
    """
    Test that `points` is a (n,3) array suitable for contour definition.
    """
    assert hasattr(points, 'shape')
    assert len(points.shape) == 2
    assert points.shape[0] >= 3
    assert points.shape[1] == 3
    assert len(set(points[:, (2)])) == 1
