How to use the ng-chat.ChatParticipantType.User function in ng-chat

import { ChatAdapter, IChatGroupAdapter, User, Group, Message, ChatParticipantStatus, ParticipantResponse, ParticipantMetadata, ChatParticipantType, IChatParticipant } from 'ng-chat';
import { Observable, of } from 'rxjs';
import { delay } from "rxjs/operators";

export class DemoAdapter extends ChatAdapter implements IChatGroupAdapter
{
    public static mockedParticipants: IChatParticipant[] = [
    {
        participantType: ChatParticipantType.User,
        id: 1,
        displayName: "Arya Stark",
        avatar: "https://66.media.tumblr.com/avatar_9dd9bb497b75_128.pnj",
        status: ChatParticipantStatus.Online
    },
    {
        participantType: ChatParticipantType.User,
        id: 2,
        displayName: "Cersei Lannister",
        avatar: null,
        status: ChatParticipantStatus.Online
    },
    {
        participantType: ChatParticipantType.User,
        id: 3,
        displayName: "Daenerys Targaryen",

{
        participantType: ChatParticipantType.User,
        id: 1,
        displayName: "Arya Stark",
        avatar: "https://66.media.tumblr.com/avatar_9dd9bb497b75_128.pnj",
        status: ChatParticipantStatus.Online
    },
    {
        participantType: ChatParticipantType.User,
        id: 2,
        displayName: "Cersei Lannister",
        avatar: null,
        status: ChatParticipantStatus.Online
    },
    {
        participantType: ChatParticipantType.User,
        id: 3,
        displayName: "Daenerys Targaryen",
        avatar: "https://68.media.tumblr.com/avatar_d28d7149f567_128.png",
        status: ChatParticipantStatus.Busy
    },
    {
        participantType: ChatParticipantType.User,
        id: 4,
        displayName: "Eddard Stark",
        avatar: "https://pbs.twimg.com/profile_images/600707945911844864/MNogF757_400x400.jpg",
        status: ChatParticipantStatus.Offline
    },
    {
        participantType: ChatParticipantType.User,
        id: 5,
        displayName: "Hodor",