How to use the vscode-azureextensionui.LocationListStep.setLocation function in vscode-azureextensionui

public async prompt(wizardContext: IAppServiceWizardContext): Promise {
        // Cache hosting plan separately per subscription
        const options: IAzureQuickPickOptions = { placeHolder: localize('selectPlan', 'Select a {0} App Service plan.', getWebsiteOSDisplayName(nonNullProp(wizardContext, 'newSiteOS'))), id: `AppServicePlanListStep/${wizardContext.subscriptionId}` };
        wizardContext.plan = (await ext.ui.showQuickPick(this.getQuickPicks(wizardContext), options)).data;

        wizardContext.telemetry.properties.newPlan = String(!wizardContext.plan);
        if (wizardContext.plan) {
            await LocationListStep.setLocation(wizardContext, wizardContext.plan.location);
        }
    }

if (await fse.pathExists(path.join(fsPath, 'package.json'))) {
            wizardContext.recommendedSiteRuntime = [LinuxRuntimes.node];
        } else if (await fse.pathExists(path.join(fsPath, 'requirements.txt'))) {
            // requirements.txt are used to pip install so a good way to determine it's a Python app
            wizardContext.recommendedSiteRuntime = [LinuxRuntimes.python];
        }
        actionContext.properties.recommendedSiteRuntime = wizardContext.recommendedSiteRuntime ? wizardContext.recommendedSiteRuntime.join(',') : undefined;
    }

    if (!advancedCreation) {
        await LocationListStep.setLocation(wizardContext, 'centralus');
        if (isJavaProject) {
            // considering high resource requirement for Java applications, a higher plan sku is set here
            wizardContext.newPlanSku = { name: 'P1v2', tier: 'PremiumV2', size: 'P1v2', family: 'P', capacity: 1 };
            // to avoid 'Requested features are not supported in region' error
            await LocationListStep.setLocation(wizardContext, 'westeurope');
        }
        // we only set the OS for the non-advanced creation scenario
        // tslint:disable-next-line:strict-boolean-expressions
        if (wizardContext.recommendedSiteRuntime) {
            wizardContext.newSiteOS = WebsiteOS.linux;
        } else {
            await workspace.findFiles('*.csproj').then((files: Uri[]) => {
                if (files.length > 0) {
                    wizardContext.newSiteOS = WebsiteOS.windows;
                }
            });
        }
    }
}

];
    }
    // only detect if one workspace is opened
    if (workspace.workspaceFolders && workspace.workspaceFolders.length === 1) {
        const fsPath: string = workspace.workspaceFolders[0].uri.fsPath;
        if (await fse.pathExists(path.join(fsPath, 'package.json'))) {
            wizardContext.recommendedSiteRuntime = [LinuxRuntimes.node];
        } else if (await fse.pathExists(path.join(fsPath, 'requirements.txt'))) {
            // requirements.txt are used to pip install so a good way to determine it's a Python app
            wizardContext.recommendedSiteRuntime = [LinuxRuntimes.python];
        }
        actionContext.properties.recommendedSiteRuntime = wizardContext.recommendedSiteRuntime ? wizardContext.recommendedSiteRuntime.join(',') : undefined;
    }

    if (!advancedCreation) {
        await LocationListStep.setLocation(wizardContext, 'centralus');
        if (isJavaProject) {
            // considering high resource requirement for Java applications, a higher plan sku is set here
            wizardContext.newPlanSku = { name: 'P1v2', tier: 'PremiumV2', size: 'P1v2', family: 'P', capacity: 1 };
            // to avoid 'Requested features are not supported in region' error
            await LocationListStep.setLocation(wizardContext, 'westeurope');
        }
        // we only set the OS for the non-advanced creation scenario
        // tslint:disable-next-line:strict-boolean-expressions
        if (wizardContext.recommendedSiteRuntime) {
            wizardContext.newSiteOS = WebsiteOS.linux;
        } else {
            await workspace.findFiles('*.csproj').then((files: Uri[]) => {
                if (files.length > 0) {
                    wizardContext.newSiteOS = WebsiteOS.windows;
                }
            });