code: def test_from_pretrained_revision(self):
      tokenizer = Tokenizer.from_pretrained("anthony/tokenizers-test")
      output = tokenizer.encode(
          "Hey there dear friend!", add_special_tokens=False
      )
      assert output.tokens == ["hey", "there", "dear", "friend", "!"]
  
      tokenizer = Tokenizer.from_pretrained(
          "anthony/tokenizers-test", revision="gpt-2"
      )
      output = tokenizer.encode(
          "Hey there dear friend!", add_special_tokens=False
      )
      assert output.tokens == ["Hey", "Ġthere", "Ġdear", "Ġfriend", "!"]
  
imports: import pickle
  import numpy
  import pytest
  from tokenizers import AddedToken, Encoding, Tokenizer
  from tokenizers.implementations import BertWordPieceTokenizer
  from tokenizers.models import BPE, Model, WordPiece, Unigram
  from tokenizers.normalizers import Lowercase
  from tokenizers.pre_tokenizers import ByteLevel
  from tokenizers.processors import BertProcessing, RobertaProcessing
  from ..utils import bert_files, data_dir, multiprocessing_with_parallelism, roberta_files
label_desc: Use image node_id 15 for calling the TestTokenizer obj's underlying member method code with example usage: obj.test_from_pretrained_revision() without return types