code: def test_more_segments_than_pixels():
      rng = np.random.default_rng(0)
      img = np.zeros((20, 21))
      img[:10, :10] = 0.33
      img[10:, :10] = 0.67
      img[10:, 10:] = 1.00
      img += 0.0033 * rng.normal(size=img.shape)
      img[img > 1] = 1
      img[img < 0] = 0
      seg = slic(
          img,
          sigma=0,
          n_segments=500,
          compactness=1,
          channel_axis=None,
          convert2lab=False,
          start_label=0,
      )
      assert np.all(seg.ravel() == np.arange(seg.size))
  
imports: from itertools import product
  import numpy
  import pytest
  from numpy.testing import assert_equal
  from skimage import data, filters, img_as_float
  from skimage._shared.testing import run_in_parallel, expected_warnings
  from skimage.segmentation import slic
label_desc: Use image node_id 14 for calling a global function with example usage: test_more_segments_than_pixels() without return types