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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_config(self, host, port, unix_socket, auth, config_key):
 """Return config string from specified Redis instance and config key :param str host: redis host :param int port: redis port :param str host: redis config_key :rtype: str """


        client = self._client(host, port, unix_socket, auth)
        if client is None:
            return None

        config_value = client.config_get(config_key)
        del client
        return config_value