code: func (api UsersAPI) ValidateEmailAddress(w http.ResponseWriter, r *http.Request) {
  	username := mux.Vars(r)["username"]
  	label := mux.Vars(r)["label"]
  	userMgr := user.NewManager(r)
  	lang := r.FormValue("lang")
  	if lang == "" {
  		lang = organization.DefaultLanguage
  	}
  	userobj, err := userMgr.GetByName(username)
  	if err != nil {
  		http.Error(w, http.StatusText(http.StatusNotFound), http.StatusNotFound)
  		return
  	}
  
  	email, err := userobj.GetEmailAddressByLabel(label)
  	if err != nil {
  		http.Error(w, http.StatusText(http.StatusNotFound), http.StatusNotFound)
  		return
  	}
  
  	_, err = api.EmailAddressValidationService.RequestValidation(r, username, email.EmailAddress, fmt.Sprintf("https://%s/emailvalidation", r.Host), lang)
  	w.WriteHeader(http.StatusNoContent)
  }
docs: // Validate email address is the handler for GET /users/{username}/emailaddress/{label}/validate