code: def test_custom_attr(self):
      for config in ADAPTER_CONFIG_MAP.values():
          with self.subTest(config=config.__class__.__name__):
              # create a copy to leave original untouched
              config = config.replace()
              config.dummy_attr = "test_value"
              self.assertEqual(config.dummy_attr, "test_value")
  
file_path: adapters/tests/test_adapter_config.py
imports: import json
  import unittest
  from dataclasses import FrozenInstanceError, dataclass
  from adapters import ADAPTER_CONFIG_MAP, AdapterConfig, ConfigUnion, DoubleSeqBnConfig, LoRAConfig, MAMConfig, ParBnConfig, PrefixTuningConfig, SeqBnConfig
  from transformers.testing_utils import require_torch
label_desc: Use image node_id 3 for calling the AdapterConfigTest obj's underlying member method code with example usage: obj.test_custom_attr() without return types