code: def test_preserve_comments(tmp_dir):
      from dvc.utils.serialize._toml import modify_toml
  
      contents_fmt = """\
  #A Title
  [foo]
  bar = {} # meaning of life
  baz = [1, 2]
  """
      tmp_dir.gen("params.toml", contents_fmt.format("42"))
  
      with modify_toml("params.toml") as d:
          d["foo"]["bar"] //= 2
      assert (
          tmp_dir / "params.toml"
      ).read_text() == contents_fmt.format("21")
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_preserve_comments(tmp_dir) without return types