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: client.rs
    path of file: ./repos/hyper/examples
    
    the code of the file until where you have to start completion: #![deny(warnings)]
#![warn(rust_2018_idioms)]
use std::env;

use bytes::Bytes;
use http_body_util::{BodyExt, Empty};
use hyper::Request;
use tokio::io::{self, AsyncWriteExt as _};
use tokio::net::TcpStream;

#[path = "../benches/support/mod.rs"]
mod support;
use support::TokioIo;

// A simple type alias so as to DRY.
type Result<T> = std::result::Result<T, Box<dyn std::error::Error + Send + Sync>>;

#[tokio::main]
async fn main() -> Result<()> {
    pretty_env_logger::init();

    // Some simple CLI args requirements...
    let url = match env::args().nth(1) {
        Some(url) => url,
        None => {
            println!("Usage: client <url>");
            return Ok(());
        }
    };

    // HTTPS requires picking a TLS implementation, so give a better
    // warning if the user tries to request an 'https' URL.
    let url = url.parse::<hyper::Uri>().unwrap();
    if url.scheme_str() != Some("http") {
        println!("This example only works with 'http' URLs.");
        return Ok(());
    }

    fetch_url(url).await
}

async fn fetch_url(url: hyper::Uri) -> Result<()> {
    let host = url.host().expect("uri has no host");
    let port = url.port_u16().unwrap_or(80);
  
    
async fn fetch_url(url: hyper::Uri) -> Result<()> {
    let host = url.host().expect("uri has no host");
    let port = url.port_u16().unwrap_or(80);
    let addr = format!("{}:{}", host, port);
    let stream = TcpStream::connect(addr).await?;
    let io = TokioIo::new(stream);

    let (mut sender, conn) = hyper::client::conn::http1::handshake(io).await?;
    tokio::task::spawn(async move {
        if let Err(err) = conn.await {
            println!("Connection failed: {:?}", err);
        }
    });

    let authority = url.authority().unwrap().clone();

    let path = url.path();
    let req = Request::builder()
        .uri(path)
        .header(hyper::header::HOST, authority.as_str())
        .body(Empty::<Bytes>::new())?;

    let mut res = sender.send_request(req).await?;

    println!("Response: {}", res.status());
    println!("Headers: {:#?}\n", res.headers());

    // Stream the body, writing each chunk to stdout as we get it
    // (instead of buffering and printing at the end).
    while let Some(next) = res.frame().await {
        let frame = next?;
        if let Some(chunk) = frame.data_ref() {
            io::stdout().write_all(&chunk).await?;
        }
    }

    println!("\n\nDone!");

    Ok(())
}