code: def tearDown(self):
      copyfile(self.bk_db, self.ori_db)
      # clean test files
      os.remove(self.bk_db)
      if os.path.isfile(os.path.join(os.getcwd(), "exp2.pkl")):
          os.remove(os.path.join(os.getcwd(), "exp2.pkl"))
  
imports: import unittest
  import os
  from shutil import copyfile, rmtree
  from subprocess import call
  from aup import compression, Experiment, BasicConfig
  from aup.utils import get_default_username
  from aup.compression.utils import verify_compression_config, run_non_automatic_experiment, adjust_compression_config
label_desc: Use image node_id 2 for calling the CompressorMainTest obj's underlying member method code with example usage: obj.tearDown() without return types