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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 request_timeout_hint(timeout_hint):
 """Decorator; add recommended client timeout hint to a request for request Useful for requests that take longer than average to reply. Hint is provided to clients via ?request-timeout-hint. Note this is only exposed if the device server sets the protocol version to KATCP v5.1 or higher and enables the REQUEST_TIMEOUT_HINTS flag in its PROTOCOL_INFO class attribute Parameters timeout_hint : float (seconds) or None How long the decorated request should reasonably take to reply. No timeout hint if None, similar to never using the decorator, provided for consistency. Examples -------- """

    if timeout_hint is not None:
        timeout_hint = float(timeout_hint)

    def decorator(handler):
        handler.request_timeout_hint = timeout_hint
        return handler

    return decorator