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: h3_simple.rs
    path of file: ./repos/reqwest/examples
    
    the code of the file until where you have to start completion: #![deny(warnings)]

// This is using the `tokio` runtime. You'll need the following dependency:
//
// `tokio = { version = "1", features = ["full"] }`
#[cfg(feature = "http3")]
#[cfg(not(target_
    
async fn main() -> Result<(), reqwest::Error> {
    use http::Version;
    use reqwest::{Client, IntoUrl, Response};

    async fn get<T: IntoUrl + Clone>(url: T) -> reqwest::Result<Response> {
        Client::builder()
            .http3_prior_knowledge()
            .build()?
            .get(url)
            .version(Version::HTTP_3)
            .send()
            .await
    }

    // Some simple CLI args requirements...
    let url = match std::env::args().nth(1) {
        Some(url) => url,
        None => {
            println!("No CLI URL provided, using default.");
            "https://hyper.rs".into()
        }
    };

    eprintln!("Fetching {url:?}...");

    let res = get(url).await?;

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

    let body = res.text().await?;

    println!("{body}");

    Ok(())
}