code: def tearDownClass(cls):
      shutil.rmtree(cls.save_root)
  
imports: import os
  import shutil
  import unittest
  import numpy
  from anago.preprocessing import IndexTransformer, pad_nested_sequences
label_desc: Use image node_id 3 for calling the TestIndexTransformer obj's underlying member method code with example usage: obj.tearDownClass(cls) without return types