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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 send_request(self, req):
 """ Make a synchronous request. Set req.sync to True, send it to a Ryu application specified by req.dst, and block until receiving a reply. Returns the received reply. The argument should be an instance of EventRequestBase. """


        assert isinstance(req, EventRequestBase)
        req.sync = True
        req.reply_q = hub.Queue()
        self.send_event(req.dst, req)
        # going to sleep for the reply
        return req.reply_q.get()