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: h2.rs
    path of file: ./repos/linkerd2-proxy/linkerd/proxy/http/src
    
    the code of the file until where you have to start completion: use crate::trace;
use futures::prelude::*;
pub use h2::{Error as H2Error, Reason};
use hyper::{
    body::HttpBody,
    client::conn::{self, SendRequest},
};
use linkerd_error::{Error, Result};
use linkerd_stack::{MakeConnection, Service};
use std::{
    marker::PhantomData,
    pin::Pin,
    task::{Context, Poll},
    time::Duration,
};
use tracing::instrument::Instrument;
use tracing::{debug, debug_span, trace_span};

#[derive(Copy, Clone, Debug, Default)]
pub struct Settings {
    pub initial_stream_window_size: Option<u32>,
    pub initial_
    
    fn call(&mut self, mut req: http::Request<B>) -> Self::Future {
        debug_assert_eq!(
            req.version(),
            http::Version::HTTP_2,
            "request version should be HTTP/2",
        );

        // A request translated from HTTP/1 to 2 might not include an
        // authority. In order to support that case, our h2 library requires
        // the version to be dropped down from HTTP/2, as a form of us
        // explicitly acknowledging that its not a normal HTTP/2 form.
        if req.uri().authority().is_none() {
            *req.version_mut() = http::Version::HTTP_11;
        }

        self.tx.send_request(req)
    }