how to get the first and last keys from a KV?

async function getFirstAndLast(KV: KVNamespace) {
    let listResult = await KV.list();
    const first = listResult.keys[0];
    while(!listResult.list_complete) {
        listResult = await KV.list({cursor: listResult.cursor});
    }
    const last = listResult.keys[listResult.keys.length - 1];
    return { first, last };
}

async function getFirstAndLast(KV: KVNamespace) {
    let listResult = await KV.list();
    const first = listResult.keys[0];
    while(!listResult.list_complete) {
        listResult = await KV.list({cursor: listResult.cursor});
    }
    const last = listResult.keys[listResult.keys.length - 1];
    return { first, last };
}