code: def test_special_tokens_mask_input_pairs(self):
      tokenizers = self.get_tokenizers(do_lower_case=False)
      for tokenizer in tokenizers:
          with self.subTest(f"{tokenizer.__class__.__name__}"):
              words, boxes = self.get_words_and_boxes()
              encoded_sequence = tokenizer.encode(
                  words, boxes=boxes, add_special_tokens=False
              )
              encoded_sequence_dict = tokenizer.encode_plus(
                  words,
                  boxes=boxes,
                  add_special_tokens=True,
                  return_special_tokens_mask=True,
                  # add_prefix_space=False,
              )
              encoded_sequence_w_special = encoded_sequence_dict[
                  "input_ids"
              ]
              special_tokens_mask = encoded_sequence_dict[
                  "special_tokens_mask"
              ]
              self.assertEqual(
                  len(special_tokens_mask),
                  len(encoded_sequence_w_special),
              )
  
              filtered_sequence = [
                  (x if not special_tokens_mask[i] else None)
                  for i, x in enumerate(encoded_sequence_w_special)
              ]
              filtered_sequence = [
                  x for x in filtered_sequence if x is not None
              ]
              self.assertEqual(encoded_sequence, filtered_sequence)
  
imports: import inspect
  import shutil
  import tempfile
  import unittest
  from typing import List
  from transformers import AddedToken, LayoutXLMTokenizerFast, SpecialTokensMixin, is_tf_available, is_torch_available, logging
  from transformers.models.layoutxlm.tokenization_layoutxlm import LayoutXLMTokenizer
  from transformers.testing_utils import get_tests_dir, is_pt_tf_cross_test, require_pandas, require_scatter, require_sentencepiece, require_tokenizers, require_torch, slow
  from ...test_tokenization_common import SMALL_TRAINING_CORPUS, TokenizerTesterMixin, filter_non_english, merge_model_tokenizer_mappings
label_desc: Use image node_id 27 for calling the LayoutXLMTokenizationTest obj's underlying member method code with example usage: obj.test_special_tokens_mask_input_pairs() without return types