code: func NewMetricsClient(caCertificatePath string, iamConfigPath string) (*http.Client, error) {
  	client := &http.Client{}
  	tr, err := getTransport(caCertificatePath)
  	if err != nil {
  		return client, err
  	}
  	client.Transport = tr
  
  	if len(iamConfigPath) != 0 {
  		rt, err := transport.NewRoundTripper(
  			client.Transport,
  			transport.OptionReadIAMConfig(iamConfigPath))
  		if err != nil {
  			log.Fatal(err)
  		}
  		client.Transport = rt
  	}
  
  	return client, nil
  }
docs: // NewMetricsClient returns a client with a transport using dcos-go/jwt/transport for
  // secure communications if a IAM configuration is present. It uses a verified cert if
  // present and skips verification if not present.