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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 replicas(self):
 """ returns all the replicas for a feature service """

        params = {
            "f" : "json",

        }
        url = self._url + "/replicas"
        return self._get(url, params,
                         securityHandler=self._securityHandler,
                         proxy_url=self._proxy_url,
                         proxy_port=self._proxy_port)