How to use the @nebular/theme.NbSidebarModule.forRoot function in @nebular/theme

BrowserModule,
    FormsModule,
    HttpClientModule,
    AppRoutingModule,
    TranslateModule.forRoot({
      loader: {
        provide: TranslateLoader,
        useFactory: (HttpLoaderFactory),
        deps: [HttpClient]
      }
    }),
    BrowserAnimationsModule,
    NbThemeModule.forRoot({ name: 'cosmic' }),
    NbLayoutModule,
    NbEvaIconsModule,
    NbSidebarModule.forRoot(), // NbSidebarModule.forRoot(), //if this is your app.module
    NbButtonModule,
    NbActionsModule,
    NbSearchModule,
    NbIconModule,
    NbMenuModule.forRoot(),
    NbTooltipModule,
    NbCardModule,
    NbInputModule,
    NbCheckboxModule,
    NbSelectModule,
    NbDialogModule.forRoot(),
    NgxMaskModule.forRoot(),
    NbToastrModule.forRoot(),
    ReactiveFormsModule,
    NbAlertModule,
    FormlyModule.forRoot(),

@NgModule({
  imports: [
    BrowserModule,
    BrowserAnimationsModule,
    FormsModule,
    HttpClientModule,
    NbSidebarModule,
    NbCardModule,
    NbLayoutModule,
    NbTabsetModule,
    NbCheckboxModule,
    NbProgressBarModule,
    NbMenuModule.forRoot(),
    NbThemeModule.forRoot(),
    NgdThemeModule.forRoot(),
    NbSidebarModule.forRoot(),
    RouterModule.forRoot(routes, { useHash: false }),
  ],
  declarations: [
    NgdAppComponent,
  ],
  providers: [
    Title,
    { provide: STRUCTURE, useValue: structure },
    { provide: DOCS, useValue: docs },
  ],
  entryComponents: [
  ],
  bootstrap: [NgdAppComponent],
})
export class AppModule {
}

import { SidebarTwoTestComponent } from './sidebar-two-test.component';

@NgModule({
  declarations: [
    SidebarCompactedComponent,
    SidebarFixedComponent,
    SidebarOneTestComponent,
    SidebarRightComponent,
    SidebarShowcaseComponent,
    SidebarTestComponent,
    SidebarThreeTestComponent,
    SidebarToggleComponent,
    SidebarTwoTestComponent,
  ],
  imports: [
    NbSidebarModule.forRoot(),
    NbLayoutModule,
    NbButtonModule,
    SidebarRoutingModule,
  ],
})
export class SidebarModule {}

import { SearchShowcaseComponent } from './search-showcase.component';
import { SearchTestComponent } from './search-test.component';
import { SearchWithInputEventComponent } from './search-with-input-event.component';

@NgModule({
  declarations: [
    SearchCustomizedTestComponent,
    SearchEventComponent,
    SearchShowcaseComponent,
    SearchTestComponent,
    SearchWithInputEventComponent,
  ],
  imports: [
    NbSearchModule,
    NbLayoutModule,
    NbSidebarModule.forRoot(),
    NbCardModule,
    SearchRoutingModule,
  ],
})
export class SearchModule {}

@NgModule({
  imports: [
    BrowserModule,
    BrowserAnimationsModule,
    FormsModule,
    HttpClientModule,
    NbSidebarModule,
    NbCardModule,
    NbLayoutModule,
    NbTabsetModule,
    NbCheckboxModule,
    NbProgressBarModule,
    NbMenuModule.forRoot(),
    NbThemeModule.forRoot(),
    NgdThemeModule.forRoot(),
    NbSidebarModule.forRoot(),
    RouterModule.forRoot(routes, { useHash: false }),
  ],
  declarations: [
    NgdAppComponent,
  ],
  providers: [
    Title,
    { provide: STRUCTURE, useValue: structure },
    { provide: DOCS, useValue: docs },
    { provide: EXAMPLES_STRUCTURE, useValue: examples },
  ],
  entryComponents: [
  ],
  bootstrap: [NgdAppComponent],
})
export class AppModule {

NbSidebarModule,
  NbToastrModule,
  NbWindowModule,
} from '@nebular/theme';

@NgModule({
  declarations: [AppComponent],
  imports: [
    BrowserModule,
    BrowserAnimationsModule,
    HttpClientModule,
    AppRoutingModule,

    ThemeModule.forRoot(),

    NbSidebarModule.forRoot(),
    NbMenuModule.forRoot(),
    NbDatepickerModule.forRoot(),
    NbDialogModule.forRoot(),
    NbWindowModule.forRoot(),
    NbToastrModule.forRoot(),
    NbChatModule.forRoot({
      messageGoogleMapKey: 'AIzaSyA_wNuCzia92MAmdLRzmqitRGvCF7wCZPY',
    }),
    CoreModule.forRoot(),
  ],
  bootstrap: [AppComponent],
  providers: [
    { provide: APP_BASE_HREF, useValue: '/' },
  ],
})
export class AppModule {

beforeEach(() => {
    TestBed.configureTestingModule({
      imports: [
        RouterTestingModule.withRoutes([]),
        NoopAnimationsModule,
        NbThemeModule.forRoot(),
        NbSidebarModule.forRoot(),
        NbMenuModule.forRoot(),
      ],
      declarations: [ SidebarExpandTestComponent ],
    });
  });