code: def test_gaussian_small_sigma():
      im = np.arange(128 * 4).reshape((16, -1))
      with pytest.raises(ValueError):
          mh.gaussian_filter(im, 0.01)
  
imports: import numpy
  import mahotas
  import mahotas.convolve
  import mahotas
  from mahotas.convolve import convolve1d, gaussian_filter
  import mahotas._filters
  from mahotas.tests.utils import luispedro_jpg
  import pytest
label_desc: Use image node_id 22 for calling a global function with example usage: test_gaussian_small_sigma() without return types