code: def testEmptyStringSingle(self):
      test_value = constant_op.constant([b""])
      expected_tokens = [[]]
      expected_offset_starts = [[]]
      expected_offset_ends = [[]]
      tokens = self.whitespace_tokenizer.tokenize(test_value)
      self.assertAllEqual(tokens, expected_tokens)
      (
          tokens,
          starts,
          ends,
      ) = self.whitespace_tokenizer.tokenize_with_offsets(test_value)
      self.assertAllEqual(tokens, expected_tokens)
      self.assertAllEqual(starts, expected_offset_starts)
      self.assertAllEqual(ends, expected_offset_ends)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import numpy
  import tensorflow
  import tensorflow_text
  from tensorflow.lite.python import interpreter
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops.ragged import ragged_factory_ops
  from tensorflow.python.platform import test
  from tensorflow_text.python.ops.whitespace_tokenizer import WhitespaceTokenizer
label_desc: Use image node_id 14 for calling the WhitespaceTokenizerOpTest obj's underlying member method code with example usage: obj.testEmptyStringSingle() without return types