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: lib.rs
    path of file: ./repos/fastn/fastn-update/src
    
    the code of the file until where you have to start completion: use snafu::prelude::*;

extern crate self as fastn_update;

mod utils;

#[derive(Snafu, Debug)]
pub enum ManifestError {
    #[snafu(display("Failed to download manifest.json for package '{package}'"))]
    DownloadManifest {
        package: String,
        source: fastn_core::Error,
    },
    #[snafu(display("Missing archive url in manifest.json for package '{package}'"))]
    NoZipUrl { package: String },
    #[snafu(display("Fai
    
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        use colored::*;

        match self {
            CheckError::WriteDuringCheck { package, file } => {
                write!(
                    f,
                    "{}\n\nThe package '{}' is out of sync with the FASTN.ftd file.\n\nFile: '{}'\nOperation: {}",
                    "Error: Out of Sync Package".red().bold(),
                    package,
                    file,
                    "Write Attempt".yellow()
                )
            }
        }
    }