code: def test_file_backed(self):
      with testing.tmp_dir(self.get_temp_dir()) as tmp_dir:
          vocab_fname = os.path.join(tmp_dir, "vocab")
          encoder = text_encoder.TokenTextEncoder(
              vocab_list=["hi", "bye", ZH_HELLO]
          )
          encoder.save_to_file(vocab_fname)
          file_backed_encoder = (
              text_encoder.TokenTextEncoder.load_from_file(vocab_fname)
          )
          self.assertEqual(encoder.tokens, file_backed_encoder.tokens)
  
imports: from __future__ import unicode_literals
  import os
  from absl.testing import parameterized
  import numpy
  from tensorflow_datasets import testing
  from tensorflow_datasets.core.deprecated.text import text_encoder
label_desc: Use image node_id 5 for calling the TokenTextEncoderTest obj's underlying member method code with example usage: obj.test_file_backed() without return types