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: build.rs
    path of file: ./repos/slint/internal/compiler
    
    the code of the file until where you have to start completion: // Copyright Â© SixtyFPS GmbH <info@slint.dev>
// SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-Slint-Royalty-free-1.1 OR LicenseRef-Slint-commercial

use std::fs::read_dir;
use std::io::{BufWriter, Write};
use std::path::{Path, PathBuf};

fn main() -> std::io::Result<()> {
    let mut library_dir = PathBuf::from(std::env::var_os("CARGO_MANIFEST_DIR").unwrap());
    library_dir.push("widgets");

    println!("cargo:rerun-if-changed={}", library_dir.display());

    let output_file_path = Path::new(&std::env::var_os("OUT_DIR").unwrap())
        .join(Path::new("included_library").with_extension("rs"));

    let mut file = BufWriter::new(std::fs::File::create(&output_file_path)?);
    write!(
        file,

    
fn process_style(path: &Path) -> std::io::Result<String> {
    let library_files: Vec<PathBuf> = read_dir(path)?
        .filter_map(Result::ok)
        .filter(|entry| {
            entry.file_type().map_or(false, |f| f.is_file())
                && entry
                    .path()
                    .extension()
                    .map(|ext| {
                        ext == std::ffi::OsStr::new("slint")
                            || ext == std::ffi::OsStr::new("60")
                            || ext == std::ffi::OsStr::new("svg")
                            || ext == std::ffi::OsStr::new("svgz")
                    })
                    .unwrap_or_default()
        })
        .map(|entry| entry.path())
        .collect();

    Ok(library_files
        .iter()
        .map(|file| {
            format!(
                "&BuiltinFile {{path: r#\"{}\"# , contents: include_bytes!(r#\"{}\"#)}}",
                file.file_name().unwrap().to_string_lossy(),
                file.display()
            )
        })
        .collect::<Vec<_>>()
        .join(","))
}