{"ast_node_type":"variable","tokens":[{"end":88,"kind":"keyword","start":0,"text":"let"}]}
    let micros_since_unix_epoch = match u64::from_str_radix(s, INT_ENCODE_BASE as u32) {
fn string_to_timestamp(s: &str) -> Result<SystemTime, &'static str> {
        Ok(micros) => micros,