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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 set_ioloop(self, ioloop=None):
 """Set the tornado IOLoop to use. Sets the tornado.ioloop.IOLoop instance to use, defaulting to IOLoop.current(). If set_ioloop() is never called the IOLoop is started in a new thread, and will be stopped if self.stop() is called. Notes ----- Must be called before start() is called. """

        self._server.set_ioloop(ioloop)
        self.ioloop = self._server.ioloop