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: download_db.rs
    path of file: ./repos/ritual/ritual/src
    
    the code of the file until where you have to start completion: // inspired by https://github.com/Xion/cargo-download/

use crate::database::CRATE_DB_FILE_NAME;
use log::{info, trace};
use reqwest::header::CONTENT_LENGTH;
use ritual_common::errors::{bail, Result};
use std::io::Read;
use std::path::Path;

const CRATES_API_ROOT: &str = "https://crates.io/api/v1/crates";

pub fn download_db(crate_name: &str, crate_version: &str, path: impl AsRef<Path>) -> Result<()> {
    let download_url = format!(
        "{}/{}/{}/download",
        CRATES_API_ROOT, crate_name, crate_version
    );
    info!(
        "Downloading crate {} v{} from {}",
        crate_name, crate_version, download_url
    );
    let mut re
    
pub fn download_db(crate_name: &str, crate_version: &str, path: impl AsRef<Path>) -> Result<()> {
    let download_url = format!(
        "{}/{}/{}/download",
        CRATES_API_ROOT, crate_name, crate_version
    );
    info!(
        "Downloading crate {} v{} from {}",
        crate_name, crate_version, download_url
    );
    let mut response = reqwest::get(&download_url)?;

    let content_length: Option<usize> = response
        .headers()
        .get(CONTENT_LENGTH)
        .and_then(|content_length| content_length.to_str().ok())
        .and_then(|content_length| content_length.parse().ok());
    trace!(
        "download size: {}",
        content_length.map_or("<unknown>".into(), |cl| format!("{} bytes", cl))
    );
    let mut bytes = match content_length {
        Some(cl) => Vec::with_capacity(cl),
        None => Vec::new(),
    };
    response.read_to_end(&mut bytes)?;

    info!("Crate {} v{} downloaded", crate_name, crate_version);

    let gzip = flate2::read::GzDecoder::new(&bytes[..]);
    let mut archive = tar::Archive::new(gzip);

    for entry in archive.entries()? {
        let mut entry = entry?;
        let entry_path = entry.path()?;
        if entry_path.components().count() == 2
            && entry_path.components().nth(1).unwrap().as_os_str() == CRATE_DB_FILE_NAME
        {
            info!("Unpacking database file");
            entry.unpack(path)?;
            info!("Database file unpacked");
            return Ok(());
        }
    }

    bail!(
        "database file ({:?}) not found in crate tarball",
        CRATE_DB_FILE_NAME
    );
}