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: turbopack.rs
    path of file: ./repos/turbo/crates/turbopack/examples
    
    the code of the file until where you have to start completion: #![feature(trivial_bounds)]

use std::{
    collections::HashMap,
    env::current_dir,
    fs,
    time::{Duration, Instant},
};

use anyhow::Result;
use tokio::{spawn, time::sleep};
use turbo_tasks::{util::FormatDuration, TurboTasks, TurboTasksBackendApi, UpdateInfo, Value, Vc};
use turbo_tasks_fs::{DiskFileSystem, FileSystem};
use turbo_tasks_memory::{
    stats::{ReferenceType, Stats},
    viz::graph::{visualize_stats_tree, wrap_html},
    MemoryBackend,
};
use turbopack::{emit_with_completion, rebase::RebasedAsset, register};
use turbopack_core::{
    compile_time_info::CompileTimeInfo,
    context::AssetContext,
    environment::{Environment, ExecutionEnvironment, NodeJsEnvironment},
    file_source::FileSource,
    PROJECT_FILESYSTEM_NAME,
};
use turbopack_resolve::resolve_options_context::ResolveOptionsContext;

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

    let tt = TurboTasks::new(MemoryBackend::default());
    let start = Instant::now();

    let task = tt.spawn_root_task(|| {
        Box::pin(async {
            let root = current_dir().unwrap().to_str().unwrap().to_string();
            let disk_fs = DiskFileSystem::new(PROJECT_FILESYSTEM_NAME.to_string(), root, vec![]);
            disk_fs.await?.start_watching()?;

            // Smart Pointer cast
            let fs: Vc<Box<dyn FileSystem>> = Vc::upcast(disk_fs);
            let input = fs.root().join("demo".to_string());
            let output = fs.root().join("out".to_string());
            let entry = fs.root().join("demo/index.js".to_string());

            let source = FileSource::new(entry);
 
    
async fn main() -> Result<()> {
    register();

    let tt = TurboTasks::new(MemoryBackend::default());
    let start = Instant::now();

    let task = tt.spawn_root_task(|| {
        Box::pin(async {
            let root = current_dir().unwrap().to_str().unwrap().to_string();
            let disk_fs = DiskFileSystem::new(PROJECT_FILESYSTEM_NAME.to_string(), root, vec![]);
            disk_fs.await?.start_watching()?;

            // Smart Pointer cast
            let fs: Vc<Box<dyn FileSystem>> = Vc::upcast(disk_fs);
            let input = fs.root().join("demo".to_string());
            let output = fs.root().join("out".to_string());
            let entry = fs.root().join("demo/index.js".to_string());

            let source = FileSource::new(entry);
            let module_asset_context = turbopack::ModuleAssetContext::new(
                Vc::cell(HashMap::new()),
                CompileTimeInfo::new(Environment::new(Value::new(
                    ExecutionEnvironment::NodeJsLambda(NodeJsEnvironment::default().into()),
                ))),
                Default::default(),
                ResolveOptionsContext {
                    enable_typescript: true,
                    enable_react: true,
                    enable_node_modules: Some(fs.root()),
                    custom_conditions: vec!["development".to_string()],
                    ..Default::default()
                }
                .cell(),
                Vc::cell("default".to_string()),
            );
            let module = module_asset_context
                .process(
                    Vc::upcast(source),
                    Value::new(turbopack_core::reference_type::ReferenceType::Undefined),
                )
                .module();
            let rebased = RebasedAsset::new(module, input, output);
            emit_with_completion(Vc::upcast(rebased), output).await?;

            Ok::<Vc<()>, _>(Default::default())
        })
    });
    spawn({
        let tt = tt.clone();
        async move {
            tt.wait_task_completion(task, true).await.unwrap();
            println!("done in {}", FormatDuration(start.elapsed()));

            loop {
                let UpdateInfo {
                    duration, tasks, ..
                } = tt
                    .get_or_wait_aggregated_update_info(Duration::from_millis(100))
                    .await;
                println!("updated {} tasks in {}", tasks, FormatDuration(duration));
            }
        }
    })
    .await
    .unwrap();

    loop {
        println!("writing graph.html...");
        // create a graph
        let mut stats = Stats::new();

        let b = tt.backend();

        // graph root node
        stats.add_id(b, task);

        // graph tasks in cache
        b.with_all_cached_tasks(|task| {
            stats.add_id(b, task);
        });

        // prettify graph
        stats.merge_resolve();

        let tree = stats.treeify(ReferenceType::Child);

        // write HTML
        fs::write(
            "graph.html",
            wrap_html(&visualize_stats_tree(
                tree,
                ReferenceType::Child,
                tt.stats_type(),
            )),
        )
        .unwrap();
        println!("graph.html written");

        sleep(Duration::from_secs(10)).await;
    }
}