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: create.rs
    path of file: ./repos/erooster/crates/erooster_imap/src/commands
    
    the code of the file until where you have to start completion: // SPDX-FileCopyrightText: 2023 MTRNord
//
// SPDX-License-Identifier: Apache-2.0

use crate::{
    commands::{CommandData, Data},
    servers::state::State,
};
use erooster_core::backend::storage::{MailStorage, Storage};
use erooster_deps::{
    color_eyre::{self, eyre::ContextCompat},
    futures::{Sink, SinkExt},
    tracing::{self, error, instrument},
};

pub struct Create<'a> {
    pub data: &'a Data,
}
impl Create<'_> {
    #[instrument(skip(self, lines, storage, command_data))]
    pub async fn exec<S, E>(
        &self,
        lines: &mut S,
        storage: &Storage,
        command_data: &CommandData<'_>,
    ) -> color_eyre::eyre::Result<()>
    where
        E: std::error::Error + std::marker::Sync + std::marker::Send + 'static,
        S: Sink<S
    
    async fn test_create_not_logged_in() {
        let caps = Create {
            data: &mut Data {
                con_state: Connection {
                    state: State::NotAuthenticated,
                    secure: true,
                    username: None,
                    active_capabilities: vec![],
                },
            },
        };
        let cmd_data = CommandData {
            tag: "a1",
            command: Commands::Create,
            arguments: &["Trash"],
        };
        let (mut tx, mut rx) = mpsc::unbounded();
        let config = erooster_core::get_config(String::from("./config.yml"))
            .await
            .unwrap();
        let database = erooster_core::backend::database::get_database(&config)
            .await
            .unwrap();
        let storage = erooster_core::backend::storage::get_storage(database, config);
        let res = caps.exec(&mut tx, &storage, &cmd_data).await;
        assert!(res.is_ok(), "{:?}", res);
        assert_eq!(
            rx.next().await,
            Some(String::from("a1 NO CREATE Not authenticated"))
        );
    }