code: def test_custom_attr(self):
      for config in ADAPTERFUSION_CONFIG_MAP.values():
          with self.subTest(config=config.__class__.__name__):
              config.dummy_attr = "test_value"
              self.assertEqual(config.dummy_attr, "test_value")
  
file_path: adapters/tests/test_adapter_fusion_config.py
imports: import unittest
  from dataclasses import FrozenInstanceError
  from adapters import ADAPTERFUSION_CONFIG_MAP, AdapterFusionConfig
  from transformers.testing_utils import require_torch
label_desc: Use image node_id 3 for calling the AdapterFusionConfigTest obj's underlying member method code with example usage: obj.test_custom_attr() without return types