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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 unfederate(self, serverId):
 """ This operation unfederates an ArcGIS Server from Portal for ArcGIS """

        url = self._url + "/servers/{serverid}/unfederate".format(
            serverid=serverId)
        params = {"f" : "json"}
        return self._get(url=url,
                         param_dict=params,
                         proxy_port=self._proxy_port,
                         proxy_url=self._proxy_ur)