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_database.rs
    path of file: ./repos/risingwave/src/frontend/src/handler
    
    the code of the file until where you have to start completion: // Copyright 2024 RisingWave Labs
//
// 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.

use pgwire::pg_response::{PgResponse, StatementType};
use risingwave_sqlparser::ast::ObjectName;

use super::RwPgResponse;
use crate::binder::Binder;
use crate::catalog::CatalogError;
use crate::error::ErrorCode::PermissionDenied;
use crate::error::Result;
use crate::handler::HandlerArgs;

pub async fn handle_create_database(
    handler_args: HandlerArgs,
    database_name: ObjectName,
    if_not_exist: bool,
) -> Result<RwPgResponse> {
    let session = handler_args.session;
    let database_name = Binder::resolve_database_name(database_name)?;

    {
        let user_reader = session.env().user_info_reader();
        let reader = user_reader.read_guard();
        if let Some(info) = reader.get_user_by_name(session.user_name()) {
            if !info.can_create_db && !info.is_super {
                return Err(PermissionDenied("Do not have the privilege".to_string()).into());
            }
        } else {
            return Err(PermissionDenied("Session user is invalid".to_string()).into());
        }
    }

    {
        let catalo
    
    async fn test_create_database() {
        let frontend = LocalFrontend::new(Default::default()).await;
        let session = frontend.session_ref();
        let catalog_reader = session.env().catalog_reader();

        frontend.run_sql("CREATE DATABASE database").await.unwrap();
        {
            let reader = catalog_reader.read_guard();
            assert!(reader.get_database_by_name("database").is_ok());
        }

        frontend.run_sql("CREATE USER user WITH NOSUPERUSER NOCREATEDB PASSWORD 'md5827ccb0eea8a706c4c34a16891f84e7b'").await.unwrap();
        let user_id = {
            let user_reader = session.env().user_info_reader();
            user_reader
                .read_guard()
                .get_user_by_name("user")
                .unwrap()
                .id
        };
        let res = frontend
            .run_user_sql(
                "CREATE DATABASE database2",
                "dev".to_string(),
                "user".to_string(),
                user_id,
            )
            .await;
        assert!(res.is_err());

        frontend.run_sql("CREATE USER user2 WITH NOSUPERUSER CREATEDB PASSWORD 'md5827ccb0eea8a706c4c34a16891f84e7b'").await.unwrap();
        let user_id = {
            let user_reader = session.env().user_info_reader();
            user_reader
                .read_guard()
                .get_user_by_name("user2")
                .unwrap()
                .id
        };
        frontend
            .run_user_sql(
                "CREATE DATABASE database2",
                "dev".to_string(),
                "user2".to_string(),
                user_id,
            )
            .await
            .unwrap();
        {
            let reader = catalog_reader.read_guard();
            assert!(reader.get_database_by_name("database2").is_ok());
        }
    }