code: def test_vis_instance_segmentation(self):
      ax = vis_instance_segmentation(
          self.img,
          self.mask,
          self.label,
          self.score,
          label_names=self.label_names,
          instance_colors=self.instance_colors,
          sort_by_score=self.sort_by_score,
      )
  
      self.assertIsInstance(ax, matplotlib.axes.Axes)
  
file_path: chainercv/tests/visualizations_tests/test_vis_instance_segmentation.py
imports: import numpy
  import unittest
  from chainer import testing
  from chainercv.visualizations import vis_instance_segmentation
label_desc: Use image node_id 2 for calling the TestVisInstanceSegmentation obj's underlying member method code with example usage: obj.test_vis_instance_segmentation() without return types