code: def test_empty() -> None:
      empty = dict()
      o = DummyOpts(empty)
      assert o.foo == "thing"
      assert o.bar is None
      assert empty == {}
  
file_path: bokeh/tests/unit/bokeh/util/test_options.py
imports: from __future__ import annotations
  import pytest
  from bokeh.core.properties import Int, Nullable, String
  from bokeh.util.options import Options
label_desc: Use image node_id 1 for calling a global function with example usage: test_empty() without return types