class_docstr: test class for the load_tokenizer fn
code: def test_special_tokens_modules_to_save(self):
      # setting special_tokens to new token
      cfg = DictDefault(
          {
              "tokenizer_config": "huggyllama/llama-7b",
              "adapter": "lora",
              "special_tokens": {"bos_token": "[INST]"},
          }
      )
      with pytest.raises(
          ValueError,
          match=r".*Please set lora_modules_to_save*",
      ):
          load_tokenizer(cfg)
  
      # setting special_tokens but not changing from default
      cfg = DictDefault(
          {
              "tokenizer_config": "huggyllama/llama-7b",
              "adapter": "lora",
              "special_tokens": {"bos_token": "<s>"},
          }
      )
      load_tokenizer(cfg)
  
      # non-adapter setting special_tokens
      cfg = DictDefault(
          {
              "tokenizer_config": "huggyllama/llama-7b",
              "special_tokens": {"bos_token": "[INST]"},
          }
      )
      load_tokenizer(cfg)
  
file_path: axolotl/tests/test_tokenizers.py
imports: import unittest
  import pytest
  from axolotl.utils.dict import DictDefault
  from axolotl.utils.models import load_tokenizer
label_desc: Use image node_id 3 for calling the TestTokenizers obj's underlying member method code with example usage: obj.test_special_tokens_modules_to_save() without return types