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: test_backup.rs
    path of file: ./repos/rust-rocksdb/tests
    
    the code of the file until where you have to start completion: // Copyright 2020 Tyler Neely
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

mod util;

use pretty_assertions::assert_eq;

use rocksdb::{
    backup::{BackupEngine, BackupEngineOptions, RestoreOptions},
    Env, DB,
};
use util::DBPath;

#[test]
fn restore_from_latest() {
    // create backup
    let path = DBPath::new("restore_from_latest_test");
    let restore_path = DBPath::new("restore_from_latest_path");
    {
        let db = DB::open_default(&path).unwrap();
        assert!(db.put(b"k1", b"v1111").is_ok
    
fn restore_from_backup() {
    // create backup
    let path = DBPath::new("restore_from_backup_test");
    let restore_path = DBPath::new("restore_from_backup_path");
    {
        let db = DB::open_default(&path).unwrap();
        assert!(db.put(b"k1", b"v1111").is_ok());
        let value = db.get(b"k1");
        assert_eq!(value.unwrap().unwrap(), b"v1111");
        {
            let backup_path = DBPath::new("restore_from_latest_test_backup");
            let env = Env::new().unwrap();
            let backup_opts = BackupEngineOptions::new(&backup_path).unwrap();

            let mut backup_engine = BackupEngine::open(&backup_opts, &env).unwrap();
            assert!(backup_engine.create_new_backup(&db).is_ok());

            // check backup info
            let info = backup_engine.get_backup_info();
            assert!(!info.is_empty());
            info.iter().for_each(|i| {
                assert!(backup_engine.verify_backup(i.backup_id).is_ok());
                assert!(i.size > 0);
            });

            let backup_id = info.get(0).unwrap().backup_id;
            let mut restore_option = RestoreOptions::default();
            restore_option.set_keep_log_files(false); // true to keep log files
            let restore_status = backup_engine.restore_from_backup(
                &restore_path,
                &restore_path,
                &restore_option,
                backup_id,
            );
            assert!(restore_status.is_ok());

            let db_restore = DB::open_default(&restore_path).unwrap();
            let value = db_restore.get(b"k1");
            assert_eq!(value.unwrap().unwrap(), b"v1111");
        }
    }
}