const response = new Response(body?: string | ArrayBuffer | Blob | ReadableStream | null | undefined, init?: ResponseInit);

// response.body
readonly body: ReadableStream;

// response.bodyUsed
readonly bodyUsed: boolean;

// response.headers
readonly headers: Headers;

// response.ok
readonly ok: boolean;

// resposne.status
readonly status: number;

// resposne.statusText
readonly statusText: string;

// response.url
readonly url: string;

// response.redirected
readonly redirected: boolean;

// response.redirectUrls
readonly redirectUrls: Array<String>

response.arrayBuffer(): Promise<ArrayBuffer>;

response.blob(): Promise<Blob>;

response.clone(copyHeaders?: boolean): Request;

response.json(): Promise<object>;

response.text(): Promise<string>;

response.formData(): Promise<FormData>;

Response.error(): Response;

Response.redirect(url: string | URL, status?: number): Response;

addEventListener('fetch', (event) => {
  const response =  new Response('hello world');
  event.respondWith(response);
});