code: def test_detokenizing_with_no_tokenizer_fails(self):
      model_id = 0
      opt = {"models": ["test_model.pt"]}
      model_root = TEST_DIR
      sm = ServerModel(opt, model_id, model_root=model_root, load=True)
      with self.assertRaises(ValueError):
          sm.detokenize("hello world")
  
imports: import unittest
  from onmt.translate.translation_server import ServerModel, TranslationServer
  import os
  from textwrap import dedent
  import torch
  from onmt.translate.translator import Translator
label_desc: Use image node_id 4 for calling the TestServerModel obj's underlying member method code with example usage: obj.test_detokenizing_with_no_tokenizer_fails() without return types