code: func (api UsersAPI) ListIyoIDs(w http.ResponseWriter, r *http.Request) {
  	username := mux.Vars(r)["username"]
  	azp, _ := context.Get(r, "client_id").(string)
  
  	mgr := iyoid.NewManager(r)
  	idObj, err := mgr.GetByUsernameAndAZP(username, azp)
  	if err != nil && !db.IsNotFound(err) {
  		handleServerError(w, "listing user iyoids", err)
  		return
  	}
  	// If nothing is found we have no iyoids yet. So just create and return a template
  	// with an empty iyo ids list
  	if idObj == nil {
  		idObj = &iyoid.Identifier{
  			Username: username,
  			Azp:      azp,
  			IyoIDs:   []string{},
  		}
  	}
  
  	w.Header().Set("Content-Type", "application/json")
  	w.WriteHeader(http.StatusOK)
  	json.NewEncoder(w).Encode(idObj)
  }
docs: // ListIyoIDs is the handler for GET /users/{username}/identifiers
  // Lists the iyo ids a party has generated for a user