Function hash

crates/ruff_python_formatter/src/comments/node_key.rs:63–67

(key: NodeRefEqualityKey)

    use std::hash::{Hash, Hasher};

    fn hash(key: NodeRefEqualityKey) -> u64 {
        let mut h = DefaultHasher::default();
        key.hash(&mut h);
        h.finish()
    }

    #[test]
    fn equality() {