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: categorical.rs
    path of file: ./repos/polars/crates/polars-core/src/chunked_array/ops/sort
    
    the code of the file until where you have to start completion: use super::*;

impl CategoricalChunked {
    #[must_use]
    pub fn sort_with(&self, options: SortOptions) -> CategoricalChunked {
        assert!(
            !options.nulls_last,
            "null last not yet supported for categorical dtype"
        )
    
    pub fn arg_sort(&self, options: SortOptions) -> IdxCa {
        if self.uses_lexical_ordering() {
            let iters = [self.iter_str()];
            arg_sort::arg_sort(
                self.name(),
                iters,
                options,
                self.physical().null_count(),
                self.len(),
            )
        } else {
            self.physical().arg_sort(options)
        }
    }