Cannot locate class or function path: 'RetinaNetDetector'.

[KumoLiu]

Describe the bug

{
    "name": "ModuleNotFoundError",
    "message": "Cannot locate class or function path: 'RetinaNetDetector'.",
    "stack": "---------------------------------------------------------------------------
ModuleNotFoundError                       Traceback (most recent call last)
Cell In[1], line 8
      5 bundle_config = ConfigParser()
      6 bundle_config.read_config(config)
----> 8 a = bundle_config.get_parsed_content(\"detector\", instantiate=True)

File /workspace/Code/MONAI/monai/bundle/config_parser.py:290, in ConfigParser.get_parsed_content(self, id, **kwargs)
    288 elif not kwargs.get(\"lazy\", True):
    289     self.parse(reset=not kwargs.get(\"lazy\", True))
--> 290 return self.ref_resolver.get_resolved_content(id=id, **kwargs)

File /workspace/Code/MONAI/monai/bundle/reference_resolver.py:193, in ReferenceResolver.get_resolved_content(self, id, **kwargs)
    181 def get_resolved_content(self, id: str, **kwargs: Any) -> ConfigExpression | str | Any | None:
    182     \"\"\"
    183     Get the resolved ``ConfigItem`` by id.
    184 
   (...)
    191 
    192     \"\"\"
--> 193     return self._resolve_one_item(id=id, **kwargs)

File /workspace/Code/MONAI/monai/bundle/reference_resolver.py:171, in ReferenceResolver._resolve_one_item(self, id, waiting_list, **kwargs)
    169 # save the resolved result into `resolved_content` to recursively resolve others
    170 if isinstance(item, ConfigComponent):
--> 171     self.resolved_content[id] = item.instantiate() if kwargs.get(\"instantiate\", True) else item
    172 elif isinstance(item, ConfigExpression):
    173     run_eval = kwargs.get(\"eval_expr\", True)

File /workspace/Code/MONAI/monai/bundle/config_item.py:298, in ConfigComponent.instantiate(self, **kwargs)
    296 args = self.resolve_args()
    297 args.update(kwargs)
--> 298 return instantiate(modname, mode, **args)

File /workspace/Code/MONAI/monai/utils/module.py:261, in instantiate(__path, __mode, **kwargs)
    259 print('*****', component, '*****')
    260 if component is None:
--> 261     raise ModuleNotFoundError(f\"Cannot locate class or function path: '{__path}'.\")
    262 m = look_up_option(__mode, CompInitMode)
    263 try:

ModuleNotFoundError: Cannot locate class or function path: 'RetinaNetDetector'."
}

To Reproduce

from monai.bundle import ConfigParser

!python -m monai.bundle download lung_nodule_ct_detection --bundle_dir "/workspace/Code/tutorials"
config = "/workspace/Code/tutorials/lung_nodule_ct_detection/configs/train.json"

bundle_config = ConfigParser()
bundle_config.read_config(config)

detector = bundle_config.get_parsed_content("detector", instantiate=True)