Function split_to_struct

pub fn split_to_struct<'a, F, I>(
    ca: &'a ChunkedArray<StringType>,
    by: &'a ChunkedArray<StringType>,
    n: usize,
    op: F,
    keep_remainder: bool,
) -> Result<ChunkedArray<StructType>, PolarsError>
where
    F: Fn(&'a str, &'a str) -> I,
    I: Iterator<Item = &'a str>,