如何在Deno中获得文件校验和？

import { createHash } from "https://deno.land/std/hash/mod.ts";
import { encode } from "https://deno.land/std/encoding/base64.ts";

const file = await Deno.readFile("path/to/file");

const hash = createHash("sha256");
hash.update(file);
const checksum = hash.toString();

const base64Checksum = encode(checksum);