code: func (md *Metadata) PasscodePrompt() string {
  	// Give default in case server doesn't tell us
  	if len(md.Prompts.Passcode) == 2 && md.Prompts.Passcode[1] != "" {
  		return md.Prompts.Passcode[1]
  	}
  	var loginURL string
  	if md.Links.Login != "" {
  		loginURL = md.Links.Login
  	} else {
  		loginURL = "https://login.system.example.com"
  	}
  	return fmt.Sprintf("One Time Code ( Get one at %s/passcode )", loginURL)
  }
docs: // PasscodePrompt returns a prompt to tell the user where to get a passcode from.
  // If not present in the metadata (PCF installation don't seem to return it), will attempt to
  // contruct a plausible URL.