code: def testCreateFilesAndDirectoryEqual(self):
      spec = {
          "file1.txt": "testing1",
          "dir1": {
              "file2.txt": "testing2",
              "dir2": {"file3.txt": "testing3"},
              "dir3": {},
          },
      }
      self.createFiles(spec)
      self.assertDirectoryEqual(self._base_dir, spec)
  
imports: import os
  from unittest import mock
  import tensorflow
  from tfx.dsl.io import fileio
  from tfx.utils import io_utils
  from tensorflow.python.lib.io import file_io
label_desc: Use image node_id 6 for calling the IoUtilsTest obj's underlying member method code with example usage: obj.testCreateFilesAndDirectoryEqual() without return types