code: def test_skeleton_length():
      #
      # Soma ends at x=8, neurite ends at x=15. Length should be 7
      #
      image = numpy.zeros((20, 20), bool)
      image[9, 5:15] = True
      labels = numpy.zeros((20, 20), int)
      labels[6:12, 2:8] = 1
      workspace, module = make_workspace(labels, image)
      module.run(workspace)
      m = workspace.measurements
      ftr = "_".join(
          (
              cellprofiler.modules.measureobjectskeleton.C_OBJSKELETON,
              cellprofiler.modules.measureobjectskeleton.F_TOTAL_OBJSKELETON_LENGTH,
              IMAGE_NAME,
          )
      )
      result = m[OBJECT_NAME, ftr]
      assert len(result) == 1
      assert abs(result[0] - 5) < numpy.sqrt(
          numpy.finfo(numpy.float32).eps
      )
  
imports: import os
  import tempfile
  import traceback
  import numpy
  import six.moves
  import cellprofiler_core.image
  import cellprofiler_core.measurement
  from cellprofiler_core.constants.measurement import GROUP_NUMBER, GROUP_INDEX, COLTYPE_FLOAT, COLTYPE_INTEGER
  import cellprofiler.modules.measureobjectskeleton
  import cellprofiler_core.object
  import cellprofiler_core.pipeline
  import cellprofiler_core.preferences
  import cellprofiler_core.setting
  import cellprofiler_core.workspace
  import tests.frontend.modules
label_desc: Use image node_id 11 for calling a global function with example usage: test_skeleton_length() without return types