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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 refresh(self):
 """ refreshes a service """

        params = {"f": "json"}
        uURL = self._url + "/refresh"
        res = self._get(url=uURL, param_dict=params,
                           securityHandler=self._securityHandler,
                           proxy_port=self._proxy_port,
                           proxy_url=self._proxy_url)
        self.__init()
        return res