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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 dht_get(self, key, *keys, **kwargs):
 """Queries the DHT for its best value related to given key. There may be several different values for a given key stored in the DHT; in this context *best* means the record that is most desirable. There is no one metric for *best*: it depends entirely on the key type. For IPNS, *best* is the record that is both valid and has the highest sequence number (freshest). Different key types may specify other rules for they consider to be the *best*. Parameters key : str One or more keys whose values should be looked up Returns ------- str """

        args = (key,) + keys
        res = self._client.request('/dht/get', args, decoder='json', **kwargs)

        if isinstance(res, dict) and "Extra" in res:
            return res["Extra"]
        else:
            for r in res:
                if "Extra" in r and len(r["Extra"]) > 0:
                    return r["Extra"]
        raise exceptions.Error("empty response from DHT")