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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_mark_sent(self, requestId):
 """Set send time & clear exception from request if set, ignoring non-existent requests"""

        with self.__requests:
            try:
                req = self.__requests[requestId]
            except KeyError:
                # request might have had a response already have been removed by receiving thread
                pass
            else:
                req.exception = None
                req._send_time = monotonic()