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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_request_timeout_hint(self, req, request):
 """Return timeout hints for requests KATCP requests should generally take less than 5s to complete, but some requests are unavoidably slow. This results in spurious client timeout errors. This request provides timeout hints that clients can use to select suitable request timeouts. Parameters request : str, optional The name of the request to return a timeout hint for (the default is to return hints for all requests that have timeout hints). Returns one inform per request. Must be an existing request if specified. Informs ------- request : str The name of the request. suggested_timeout : float Suggested request timeout in seconds for the request. If `suggested_timeout` is zero (0), no timeout hint is available. Returns ------- success : {'ok', 'fail'} Whether sending the help succeeded. informs : int Number of #request-timeout-hint inform messages sent. Examples -------- :: ?request-timeout-hint #request-timeout-hint halt 5 #request-timeout-hint very-slow-request 500 !request-timeout-hint ok 5 ?request-timeout-hint moderately-slow-request #request-timeout-hint moderately-slow-request 20 !request-timeout-hint ok 1 Notes ----- ?request-timeout-hint without a parameter will only return informs for requests that have specific timeout hints, so it will most probably be a subset of all the requests, or even no informs at all. """

        timeout_hints = {}
        if request:
            if request not in self._request_handlers:
                raise FailReply('Unknown request method')
            timeout_hint = getattr(
                self._request_handlers[request], 'request_timeout_hint', None)
            timeout_hint = timeout_hint or 0
            timeout_hints[request] = timeout_hint
        else:
            for request_, handler in self._request_handlers.items():
                timeout_hint = getattr(handler, 'request_timeout_hint', None)
                if timeout_hint:
                    timeout_hints[request_] = timeout_hint

        cnt = len(timeout_hints)
        for request_name, timeout_hint in sorted(timeout_hints.items()):
            req.inform(request_name, float(timeout_hint))

        return ('ok', cnt)