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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 get_key(self, key_id):
 """ Returns a restclients.Key object for the given key ID. If the key ID isn't found, or if there is an error communicating with the KWS, a DataFailureException will be thrown. """

        url = ENCRYPTION_KEY_URL.format(key_id)
        return self._key_from_json(self._get_resource(url))