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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, refresh_token):
 """ Renew an oauth token given an appropriate refresh token. :param refresh_token: The Refresh Token :return: A tuple of (token, expiration time in unix time stamp) """

        r = requests.post(self.apiurl + "/token", params={"grant_type": "refresh_token", "client_id": self.cid,
                                                          "client_secret": self.csecret,
                                                          "refresh_token": refresh_token})

        if r.status_code != 200:
            raise ServerError

        jsd = r.json()

        return jsd['access_token'], int(jsd['expires_in']) + int(jsd['created_at'])