code: func getAddress(opts string) string {
  	optsList := strings.Split(opts, ",")
  	for i := 0; i < len(optsList); i++ {
  		if strings.HasPrefix(optsList[i], "addr=") {
  			addr := strings.SplitN(optsList[i], "=", 2)[1]
  			return addr
  		}
  	}
  	return ""
  }
docs: // getAddress finds out address/hostname from options