Class Sentinel

traitlets/__init__.py:27–37

class Sentinel(traitlets.Sentinel):  # type:ignore[name-defined, misc]
    def __init__(self, *args: _t.Any, **kwargs: _t.Any) -> None:
        super().__init__(*args, **kwargs)
        warn(
            """
            Sentinel is not a public part of the traitlets API.
            It was published by mistake, and may be removed in the future.
            """,
            DeprecationWarning,
            stacklevel=2,
        )