code: def tar_and_copy_t2t(train_dir):
    
    tf.logging.info("Tarring and pushing local Tensor2Tensor package.")
  
    output = text_encoder.native_to_unicode(shell_output(
        "pip show tensor2tensor")).split("\n")
    assert output[1].startswith("Version")
    assert output[7].startswith("Location")
    t2t_version = output[1].split(":")[1].strip()
    t2t_dir = output[7].split(":")[1].strip()
  
    # A local installation cloned from GitHub will have a setup.py file and a docs
    # folder
    is_local_t2t = all([
        tf.gfile.Exists(os.path.join(t2t_dir, fname))
        for fname in ["setup.py", "docs/cloud_mlengine.md"]
    ])
  
    if is_local_t2t:
      tf.logging.info("Found local T2T installation. Tarring directory %s",
                      t2t_dir)
    else:
      # PyPI installation
      # Create a folder with just a setup.py file pointing to the right version
      tf.logging.info("Found PyPI T2T installation. Launching tensor2tensor==%s",
                      t2t_version)
      t2t_dir = os.path.join(tempfile.gettempdir(), "tensor2tensor_tmp")
      shutil.rmtree(t2t_dir, ignore_errors=True)
      os.mkdir(t2t_dir)
      setup_fname = os.path.join(t2t_dir, "setup.py")
      setup_file_str = get_setup_file(
          name="DummyT2TPackage",
          packages=["tensor2tensor==%s" % t2t_version]
      )
      with tf.gfile.Open(setup_fname, "w") as f:
        f.write(setup_file_str)
    t2t_tar = _tar_and_copy(t2t_dir, train_dir)
    return t2t_tar
docs: Tar Tensor2Tensor and cp to train_dir.