code: func NewDatadogCollectorWithClient(client DatadogClient) func(string) metricCollector.MetricCollector {
  
  	return func(name string) metricCollector.MetricCollector {
  
  		return &DatadogCollector{
  			client: client,
  			tags:   []string{"hystrixcircuit:" + name},
  		}
  	}
  }
docs: // NewDatadogCollectorWithClient accepts an interface which allows you to
  // provide your own implementation of a statsd client, alter configuration on
  // "github.com/DataDog/datadog-go/statsd".(*Client), provide additional tags per
  // circuit-metric tuple, and add logging if you need it.