How to use the @shopify/sewing-kit-koa.getAssets function in @shopify/sewing-kit-koa

async function renderFunction(ctx: Context) {
    const logger = getLogger(ctx) || console;
    const assets = getAssets(ctx);

    const networkManager = new NetworkManager({
      headers: ctx.headers,
      cookies: ctx.request.headers.cookie || '',
    });
    const htmlManager = new HtmlManager();
    const asyncAssetManager = new AsyncAssetManager();
    const hydrationManager = new HydrationManager();

    function Providers({children}: {children: React.ReactElement}) {
      return (
        
          
            
              {children}

const {id} = body.extensions.persisted;

    if (body.query != null) {
      if (
        cacheMissBehavior === CacheMissBehavior.SendAndStore &&
        cache != null
      ) {
        await cache.set(id, body.query);
      }

      await next();
      return;
    }

    const assets = getAssets(ctx);

    const operationFromManifest =
      assets != null && assets.graphQLSource != null
        ? await assets.graphQLSource(id)
        : undefined;

    if (typeof operationFromManifest === 'string' && cache != null) {
      cache.set(id, operationFromManifest);
    }

    const operation = operationFromManifest || (cache && (await cache.get(id)));

    if (typeof operation === 'string') {
      body.query = operation;
      await next();
    } else {