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: publish_post.rs
    path of file: ./repos/diesel/examples/mysql/getting_started_step_3/src/bin
    
    the code of the file until where you have to start completion: use self::models::Post;
use diesel::prelude::*;
use diesel_demo_step_3_mysql::*;
use std::env::args;

fn main() {
    use self::schema::posts::dsl::{posts, published};

    let id = args()
        .nth(1)
    
    
fn main() {
    use self::schema::posts::dsl::{posts, published};

    let id = args()
        .nth(1)
        .expect("publish_post requires a post id")
        .parse::<i32>()
        .expect("Invalid ID");
    let connection = &mut establish_connection();

    let post = connection
        .transaction(|connection| {
            let post = posts.find(id).select(Post::as_select()).first(connection)?;

            diesel::update(posts.find(id))
                .set(published.eq(true))
                .execute(connection)?;
            Ok(post)
        })
        .unwrap_or_else(|_: diesel::result::Error| panic!("Unable to find post {}", id));

    println!("Published post {}", post.title);
}