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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 stop(self):
 """Stop a running SocketIO web server. This method must be called from a HTTP or SocketIO handler function. """

        if self.server.eio.async_mode == 'threading':
            func = flask.request.environ.get('werkzeug.server.shutdown')
            if func:
                func()
            else:
                raise RuntimeError('Cannot stop unknown web server')
        elif self.server.eio.async_mode == 'eventlet':
            raise SystemExit
        elif self.server.eio.async_mode == 'gevent':
            self.wsgi_server.stop()