class_docstr: An immutable variant of the Python dict.
class_docstr_tok: ["An","immutable","variant","of","the","Python","dict","."]
code: def __getitem__(self, key):
      v = self._dict[key]
      if isinstance(v, dict):
          return FrozenDict(v)
      return v
  
imports: import collections
  from types import MappingProxyType
  from typing import Any, Dict, Hashable, Mapping, Tuple, TypeVar, Union
  import jax
  from flax import serialization
label_desc: Use image node_id 2 for calling the FrozenDict obj's underlying member method code with example usage: obj.__getitem__(key) and returns: v, FrozenDict