code: def mypy_set_typing() -> None:
      class T(HasTraits):
          remove_cell_tags = Set(
              Unicode(),
              default_value=[],
              help=(
                  "Tags indicating which cells are to be removed,"
                  "matches tags in ``cell.metadata.tags``."
              ),
          ).tag(config=True)
  
          safe_output_keys = Set(
              config=True,
              default_value={
                  "metadata",  # Not a mimetype per-se, but expected and safe.
                  "text/plain",
                  "text/latex",
                  "application/json",
                  "image/png",
                  "image/jpeg",
              },
              help="Cell output mimetypes to render without modification",
          )
  
      t = T()
      reveal_type(Set("foo"))  # R: traitlets.traitlets.Set
      reveal_type(Set("").tag(sync=True))  # R: traitlets.traitlets.Set
      reveal_type(
          Set(None, allow_none=True)
      )  # R: traitlets.traitlets.Set
      reveal_type(
          Set(None, allow_none=True).tag(sync=True)
      )  # R: traitlets.traitlets.Set
      reveal_type(T.remove_cell_tags)  # R: traitlets.traitlets.Set
      reveal_type(t.remove_cell_tags)  # R: builtins.set[Any]
      reveal_type(T.safe_output_keys)  # R: traitlets.traitlets.Set
      reveal_type(t.safe_output_keys)
  
imports: from __future__ import annotations
  import logging
  import typing
  from abc import ABC
  import pytest
  from traitlets import Any, Bool, CInt, Dict, Enum, HasTraits, Instance, Int, List, Set, TCPAddress, Type, Unicode, Union, default, observe, validate
  from traitlets.config import Config
label_desc: Use image node_id 9 for calling a global function with example usage: mypy_set_typing() without return types