I'd like to use a method in a export function defined in a class file.

export function MSALInstanceFactory(): IPublicClientApplication {
    return new PublicClientApplication({
        auth: AzureService.getConfiguration(), <-------- Compilation Error
        cache: {
            cacheLocation: BrowserCacheLocation.LocalStorage,
            storeAuthStateInCookie: isIE, // set to true for IE 11. Remove this line to use Angular Universal
        }
    });
}

export class AzureModule { }

This is the Service Class

@Injectable()
export class AzureService {

    constructor(private identityManagerApiRestService: IdentityManagerApiRestService) { }

    getConfiguration(): BrowserAuthOptions {
        let options: BrowserAuthOptions;
        this.identityManagerApiRestService.getAuthenticationConfiguration().subscribe(response =>{
            options.clientId = response.authenticationConfiguration.clientId;
            options.authority = response.authenticationConfiguration.authority;
            options.redirectUri = response.authenticationConfiguration.redirectUri;
        });
        return options;
    }
}

How can I use AzureService.getConfiguration() method in the exported function method in the Module. I want this because the values are dynamic and they are obtained in a rest call.