code: def tearDown(self):
      shutil.rmtree(self.temp_dir)
  
imports: import numpy
  import os
  import shutil
  import tempfile
  import unittest
  from chainer import testing
  from chainer.testing import attr
  from chainercv.datasets.cityscapes.cityscapes_utils import cityscapes_labels
  from chainercv.datasets import CityscapesSemanticSegmentationDataset
  from chainercv.datasets import CityscapesTestImageDataset
  from chainercv.utils import assert_is_semantic_segmentation_dataset
  from chainercv.utils.testing.assertions.assert_is_image import assert_is_image
  from chainercv.utils import write_image
label_desc: Use image node_id 2 for calling the TestCityscapesTestImageDataset obj's underlying member method code with example usage: obj.tearDown() without return types