code: def test_run(image, module, image_set, workspace):
      module.x_name.value = "example"
  
      module.y_name.value = "MorphologicalSkeleton"
  
      module.run(workspace)
  
      actual = image_set.get_image("MorphologicalSkeleton")
  
      if image.volumetric:
          desired = skimage.morphology.skeletonize_3d(image.pixel_data)
      else:
          desired = skimage.morphology.skeletonize(image.pixel_data)
  
      numpy.testing.assert_array_equal(actual.pixel_data, desired)
  
imports: import numpy.testing
  import pytest
  import skimage.data
  import skimage.morphology
  import cellprofiler_core.image
  import cellprofiler.modules.morphologicalskeleton
label_desc: Use image node_id 2 for calling a global function with example usage: test_run(image, module, image_set, workspace) without return types