code: def testStringToIdScalar(self):
      sp = SentencepieceTokenizer(self.model)
      result = sp.string_to_id("</s>")
      self.assertAllEqual(2, result)
  
imports: import sys
  import tempfile
  from absl.testing import parameterized
  from tensorflow.python.data.ops import dataset_ops
  from tensorflow.python.eager import context
  from tensorflow.python.eager import def_function
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import errors
  from tensorflow.python.framework import tensor_spec
  from tensorflow.python.framework import test_util
  from tensorflow.python.lib.io import file_io
  from tensorflow.python.module import module
  from tensorflow.python.ops import gen_experimental_dataset_ops
  from tensorflow.python.ops.ragged import ragged_factory_ops
  from tensorflow.python.ops.ragged import ragged_gather_ops
  from tensorflow.python.platform import gfile
  from tensorflow.python.platform import test
  from tensorflow.python.saved_model import load
  from tensorflow.python.saved_model import save
  from tensorflow_text.python.ops.sentencepiece_tokenizer import SentencepieceTokenizer
label_desc: Use image node_id 8 for calling the SentencepieceTokenizerOpTest obj's underlying member method code with example usage: obj.testStringToIdScalar() without return types