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: arrow_string.rs
    path of file: ./repos/rerun/crates/re_types_core/src
    
    the code of the file until where you have to start completion: use arrow2::buffer::Buffer;

/// Convenience-wrapper around an arrow [`Buffer`] that is known to contain a
/// UTF-8 encoded string.
///
/// The arrow2 [`Buffer`] object is internally reference-counted and can be
/// easily converted back to a `&str` referencing the underlying storage.
/// This avoids some of the l
    
fn borrow_hash_is_self_hash() {
    use std::borrow::Borrow as _;
    use std::hash::{Hash as _, Hasher as _};

    let s = ArrowString::from("hello world");

    let self_hash = {
        let mut hasher = std::collections::hash_map::DefaultHasher::new();
        s.hash(&mut hasher);
        hasher.finish()
    };

    let borrowed_hash = {
        let mut hasher = std::collections::hash_map::DefaultHasher::new();
        let s: &str = s.borrow();
        s.hash(&mut hasher);
        hasher.finish()
    };

    assert_eq!(self_hash, borrowed_hash);
}