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/rust-farm/handson/submarine/src
    
    the code of the file until where you have to start completion: use bracket_lib::prelude::{main_loop, BError, BTermBuilder};
use state::State;

mod constant;
mod game_mode;
mod level;
mod player;
mod rock;
mod state;
/*
   b
    
fn main() -> BError {
    // 80X50 boyutlarında, başlığında Submarine - Red Squad yazan bir context inşa ediliyor
    let context = BTermBuilder::simple80x50()
        .with_title("Submarine - Red Squad")
        .build()?;

    // oyun motorunu, oyunun state nesnesi ile bağlıyoruz
    main_loop(context, State::new())
}