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: csvtab.rs
    path of file: ./repos/libsql/vendored/rusqlite/src/vtab
    
    the code of the file until where you have to start completion: //! CSV Virtual Table.
//!
//! Port of [csv](http://www.sqlite.org/cgi/src/finfo?name=ext/misc/csv.c) C
//! extension: `https://www.sqlite.org/csv.html`
//!
//! # Example
//!
//! ```rust,no_run
//! # use rusqlite::{Connection, Result};
//! fn example() -> Result<()> {
//!     // Note: This should be done once (usually when opening the DB).
//!     let db = Connection::open_in_memory()?;
//!     rusqlite::vtab::csvtab::load_module(&db)?;
//!     // A
    
    fn test_csv_module() -> Result<()> {
        let db = Connection::open_in_memory()?;
        csvtab::load_module(&db)?;
        db.execute_batch("CREATE VIRTUAL TABLE vtab USING csv(filename='test.csv', header=yes)")?;

        {
            let mut s = db.prepare("SELECT rowid, * FROM vtab")?;
            {
                let headers = s.column_names();
                assert_eq!(vec!["rowid", "colA", "colB", "colC"], headers);
            }

            let ids: Result<Vec<i32>> = s.query([])?.map(|row| row.get::<_, i32>(0)).collect();
            let sum = ids?.iter().sum::<i32>();
            assert_eq!(sum, 15);
        }
        db.execute_batch("DROP TABLE vtab")
    }