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: main.rs
    path of file: ./repos/templa-rs/src
    
    the code of the file until where you have to start completion: use clap::{load_yaml, App};
use reqwest::blocking::Client;
use serde_json::Value;

mod command;
mod models;
mod search;
mod size;
mod tui;
mod app;
mod scrape;

const SUBMODULES_URL: &str = "https://api
    
fn fetch_submodules() -> Result<Vec<models::structs::Submodule>, Box<dyn std::error::Error>> {
    let client = Client::builder()
        .user_agent("templa-rs, https://github.com/IEEE-VIT/templa-rs")
        .build()?;
    let response: Value = client
        .get(SUBMODULES_URL)
        .header(
            reqwest::header::ACCEPT,
            reqwest::header::HeaderValue::from_static("application/vnd.github.v3+json"),
        )
        .send()?
        .json()?;
    let encoded_body = response["content"].as_str().unwrap();
    let decoded_body = base64::decode(encoded_body.replace('\n', "")).unwrap();
    Ok(serde_json::from_slice(&decoded_body)?)
}