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/vopono/src
    
    the code of the file until where you have to start completion: #![allow(clippy::upper_case_acronyms)]
#![allow(clippy::large_enum_variant)]
#![allow(dead_code)]

mod args;
mod args_config;
mod cli_client;
mod exec;
mod list;
mod list_configs;
mod sync;

use clap::Parser;
use cli_client::CliClient;
use list::output_list;
use list_configs::print_configs;
use log::{debug, warn, LevelFilter};
use sync::{sync_menu, synch};
use vopono_core::util::clean_dead_locks;
use vopono_core::util::clean_dead_namespaces;
use vopono_core::util::elevate_privileges;
use which::which;

fn main() -> anyhow::Result<()> {
    // Get struct of args using structopt
    let app = args::App::parse();
    // Set up logging
    let mut builder = pretty_env_logger::formatted_timed_builder();
    let log_level = if app.verbose {
        LevelFilter::Debug
    } else {
        LevelFilter::Info
    };
    builder.filter_level(log_level);
    builder.init();

    let uiclient = CliClient {};
    match app.cmd {
        args::Command::Exec(cmd) => {
            clean_dead_locks()?;
            if which("pactl").is_ok() {
                let pa = vopono_core::util::pulseaudio::get_pulseaudio_server();
                if let Ok(pa) = pa {
                    std::env::set_var("PULSE_SERVE
    
fn main() -> anyhow::Result<()> {
    // Get struct of args using structopt
    let app = args::App::parse();
    // Set up logging
    let mut builder = pretty_env_logger::formatted_timed_builder();
    let log_level = if app.verbose {
        LevelFilter::Debug
    } else {
        LevelFilter::Info
    };
    builder.filter_level(log_level);
    builder.init();

    let uiclient = CliClient {};
    match app.cmd {
        args::Command::Exec(cmd) => {
            clean_dead_locks()?;
            if which("pactl").is_ok() {
                let pa = vopono_core::util::pulseaudio::get_pulseaudio_server();
                if let Ok(pa) = pa {
                    std::env::set_var("PULSE_SERVER", pa);
                } else {
                    warn!(
                        "Could not parse PULSE_SERVER from pactl info output: {:?}",
                        pa
                    );
                }
            } else {
                debug!("pactl not found, will not set PULSE_SERVER");
            }
            elevate_privileges(app.askpass)?;
            clean_dead_namespaces()?;
            exec::exec(cmd, &uiclient, app.verbose)?
        }
        args::Command::List(listcmd) => {
            clean_dead_locks()?;
            output_list(listcmd)?;
        }
        args::Command::Synch(synchcmd) => {
            // If provider given then sync that, else prompt with menu
            if synchcmd.vpn_provider.is_none() {
                sync_menu(&uiclient)?;
            } else {
                synch(
                    synchcmd.vpn_provider.unwrap().to_variant(),
                    synchcmd.protocol.map(|x| x.to_variant()),
                    &uiclient,
                )?;
            }
        }
        args::Command::Servers(serverscmd) => {
            print_configs(serverscmd)?;
        }
    }
    Ok(())
}