You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: fs_open_options.rs
    path of file: ./repos/tokio/tokio/tests
    
    the code of the file until where you have to start completion: #![warn(rust_2018_idioms)]
#![cfg(all(feature = "full", not(target_os = "wasi")))] // WASI does not support all fs operations

use std::io::Write;
use tempfile::NamedTempFile;
use tokio::fs::OpenOptions;
use tokio::io::A
    
async fn open_with_open_options_and_read() {
    let mut tempfile = NamedTempFile::new().unwrap();
    tempfile.write_all(HELLO).unwrap();

    let mut file = OpenOptions::new().read(true).open(tempfile).await.unwrap();

    let mut buf = [0; 1024];
    let n = file.read(&mut buf).await.unwrap();

    assert_eq!(n, HELLO.len());
    assert_eq!(&buf[..n], HELLO);
}