code: def testCopyDirWithTrailingSlashes(self):
      self.createFiles({"old": {"dir": {"file.txt": "testing"}}})
  
      with self.subTest("Copy old/ to new1"):
          io_utils.copy_dir(
              self.relpath("old", ""), self.relpath("new1")
          )
          self.assertDirectoryEqual(
              self.relpath("new1"), {"dir": {"file.txt": "testing"}}
          )
  
      with self.subTest("Copy old to new2/"):
          io_utils.copy_dir(
              self.relpath("old"), self.relpath("new2", "")
          )
          self.assertDirectoryEqual(
              self.relpath("new2"), {"dir": {"file.txt": "testing"}}
          )
  
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 12 for calling the IoUtilsTest obj's underlying member method code with example usage: obj.testCopyDirWithTrailingSlashes() without return types