import { io } from "https://deno.land/x/s3si@gui-v0.4.16/deps.ts";
const { BufWriterSync } = io;
Writes the contents of data into the buffer. If the contents won't fully
fit into the buffer, those bytes that can are copied into the buffer, the
buffer is the flushed to the writer and the remaining bytes are copied into
the now empty buffer.