class_docstr: Register from names to classes. In particular, we say that direct subclasses of
  ReplaceableBase are "base classes" and we register subclasses of each base class
  in a separate namespace.
code: def __init__(self) -> None:
      self._mapping: Dict[
          Type[ReplaceableBase], Dict[str, Type[ReplaceableBase]]
      ] = defaultdict(dict)
  
imports: import dataclasses
  import inspect
  import itertools
  import sys
  import warnings
  from collections import Counter, defaultdict
  from enum import Enum
  from functools import partial
  from typing import Any, Callable, Dict, get_args, get_origin, List, Optional, Tuple, Type, TypeVar, Union
  from omegaconf import DictConfig, OmegaConf, open_dict
label_desc: Use image node_id 1 to create a new _Registry object  with example: obj = _Registry()