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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 client(cls, config):
 """ Cache statsd client so it doesn't do a DNS lookup over and over """

        if not hasattr(cls, "_client"):
            cls._client = statsd.StatsClient(config.STATSD_HOST, config.STATSD_PORT, config.STATSD_PREFIX)
        return cls._client