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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 start_client(self, event=None, timeout=None):
 """ Negotiate a new SSH2 session as a client. This is the first step after creating a new `.Transport`. A separate thread is created for protocol negotiation. If an event is passed in, this method returns immediately. When negotiation is done (successful or not), the given ``Event`` will be triggered. On failure, `is_active` will return ``False``. (Since 1.4) If ``event`` is ``None``, this method will not return until negotiation is done. On success, the method returns normally. Otherwise an SSHException is raised. After a successful negotiation, you will usually want to authenticate, calling `auth_password <Transport.auth_password>` or `auth_publickey <Transport.auth_publickey>`. .. note:: `connect` is a simpler method for connecting as a client. .. note:: After calling this method (or `start_server` or `connect`), you should no longer directly read from or write to the original socket object. :param .threading.Event event: an event to trigger when negotiation is complete (optional) :param float timeout: a timeout, in seconds, for SSH2 session negotiation (optional) :raises: `.SSHException` -- if negotiation fails (and no ``event`` was passed in) """

        self.active = True
        if event is not None:
            # async, return immediately and let the app poll for completion
            self.completion_event = event
            self.start()
            return

        # synchronous, wait for a result
        self.completion_event = event = threading.Event()
        self.start()
        max_time = time.time() + timeout if timeout is not None else None
        while True:
            event.wait(0.1)
            if not self.active:
                e = self.get_exception()
                if e is not None:
                    raise e
                raise SSHException("Negotiation failed.")
            if event.is_set() or (
                timeout is not None and time.time() >= max_time
            ):
                break