// AssumeRoleWithCustomToken STS API.

	var opts []cr.CustomTokenOpt
	if expiryDuration != 0 {
		opts = append(opts, cr.CustomTokenValidityOpt(expiryDuration))
	}

	// Initialize
	li, err := cr.NewCustomTokenCredentials(stsEndpoint, token, roleArn, opts...)
	if err != nil {
		log.Fatalf("Error initializing CustomToken Identity: %v", err)
	}

	v, err := li.Get()
	if err != nil {