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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 wait_running(self, timeout=None):
 """Wait until the client is running. Parameters timeout : float in seconds Seconds to wait for the client to start running. Returns ------- running : bool Whether the client is running Notes ----- Do not call this from the ioloop, use until_running(). """

        ioloop = getattr(self, 'ioloop', None)
        if not ioloop:
            raise RuntimeError('Call start() before wait_running()')
        return self._running.wait_with_ioloop(ioloop, timeout)