class_docstr: A dict-like node with attribute-access
docstr: Set an item on the notebook.
docstr_tok: ["Set","an","item","on","the","notebook","."]
code: def __setitem__(self, key, value):
      """Set an item on the notebook."""
      if isinstance(value, Mapping) and not isinstance(
          value, NotebookNode
      ):
          value = from_dict(value)
      super().__setitem__(key, value)
  
file_path: nbformat/nbformat/notebooknode.py
imports: from __future__ import annotations
  from collections.abc import Mapping
  from ._struct import Struct
label_desc: Use image node_id 1 for calling the NotebookNode obj's underlying member method code with example usage: obj.__setitem__(key, value) without return types