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: mod.rs
    path of file: ./repos/ferrocarril/nemesis/src/server/rocket
    
    the code of the file until where you have to start completion: //! Nemesis server based on [Rocket](rocket).

use rocket::http::Status;
use rocket::request::Request;
use rocket::response::{self, Responder};
use std::io::Cursor;

use crate::server::Builder;
use crate::Error;

mod request;
mod routes;

pub fn launcher(builder: Builder) -> Result<(), Error> {
    let mut launcher = rocket::ignite();
    for (path, mount)
    
pub fn launcher(builder: Builder) -> Result<(), Error> {
    let mut launcher = rocket::ignite();
    for (path, mount) in builder.mounts.0 {
        launcher = launcher.mount(path.as_str(), routes::RackHandler::routes(&mount));
    }
    for path in builder.assets.0.keys() {
        launcher = launcher.mount(path.as_str(), routes![routes::static_asset]);
    }
    launcher = launcher.manage(builder.assets);
    let err = launcher.launch();
    // This log is only reachable if Rocket has an error during startup,
    // otherwise `rocket::ignite().launch()` blocks forever.
    error!("Failed to launch rocket: {}", err);
    Err(Error::FailedLaunch(err.to_string()))
}