code: def print_files(self):
      print("Existing files:")
      for dirpath, dirnames, filenames in os.walk(
          self.working_directory
      ):
          print(dirpath, dirnames, filenames)
  
file_path: auto-sklearn/test/test_scripts/test_metadata_generation.py
imports: import json
  import os
  import random
  import shutil
  import socket
  import subprocess
  import tempfile
  import arff
  import numpy
  from autosklearn.metrics import CLASSIFICATION_METRICS, REGRESSION_METRICS
  import unittest
label_desc: Use image node_id 2 for calling the TestMetadataGeneration obj's underlying member method code with example usage: obj.print_files() without return types