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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _unquote_or_none(s: Optional[str]) -> Optional[bytes]: # noqa: F811 """None-safe wrapper around url_unescape to handle unmatched optional groups correctly. Note that args are passed as bytes so the handler can decide what encoding to use. """

    if s is None:
        return s
    return url_unescape(s, encoding=None, plus=False)