code: def test_native_to_unicode(self):
      s = r"foo bar"
      s_unicode = text_encoder.native_to_unicode(s)
      if six.PY2:
          self.assertIsInstance(s_unicode, unicode)
      self.assertEqual(s_unicode, "foo bar")
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from __future__ import unicode_literals
  import collections
  import io
  import os
  import random
  import shutil
  import string
  import mock
  import six
  from six.moves import range
  from tensor2tensor.data_generators import text_encoder
  import tensorflow.compat.v1
label_desc: Use image node_id 1 for calling the NativeToUnicodeTest obj's underlying member method code with example usage: obj.test_native_to_unicode() without return types