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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 rename(self, new_name):
 """ Rename a key :param new_name: New name for the key (will also serve as the key's id) :returns: An updated list of added keys """

        payload = {
            'new_name': new_name
        }
        data = json.dumps(payload)
        req = self.request(self.mist_client.uri+'/keys/'+self.id, data=data)
        req.put()
        self.id = new_name
        self.mist_client.update_keys()