imports: import unittest
  from transformers import SPIECE_UNDERLINE, ReformerTokenizer, ReformerTokenizerFast
  from transformers.testing_utils import get_tests_dir, require_sentencepiece, require_tokenizers, require_torch, slow
  from transformers.utils import cached_property
  from ...test_tokenization_common import TokenizerTesterMixin
label_desc: Use image node_id 13 for calling the ReformerTokenizationTest obj's underlying member method code with example usage: obj.test_tokenizer_integration() without return types