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: tests.rs
    path of file: ./repos/polars/crates/polars-core/src
    
    the code of the file until where you have to start completion: use crate::prelude::*;

#[test]
fn test_initial_empty_sort() -> PolarsResult<()> {
    // https://github
    
fn test_initial_empty_sort() -> PolarsResult<()> {
    // https://github.com/pola-rs/polars/issues/1396
    let data = vec![1.3; 42];
    let mut series = Series::new("data", Vec::<f64>::new());
    let series2 = Series::new("data2", data.clone());
    let series3 = Series::new("data3", data);
    let df = DataFrame::new(vec![series2, series3])?;

    for column in df.get_columns().iter() {
        series.append(column)?;
    }
    series.f64()?.sort(false);
    Ok(())
}