code: func NewNetDevCollector() (Collector, error) {
  	pattern := regexp.MustCompile(*netdevIgnoredDevices)
  	return &netDevCollector{
  		subsystem:             "network",
  		ignoredDevicesPattern: pattern,
  		metricDescs:           map[string]*prometheus.Desc{},
  	}, nil
  }
docs: // NewNetDevCollector returns a new Collector exposing network device stats.