{"ast_node_type":"function","tokens":[{"end":84,"kind":"keyword","start":0,"text":"fn"}]}
fn find_delimiters(cx: &LateContext<'_>, span: Span) -> Option<(Span, Span, char)> {
/// and the type of (opening) delimiter used.
    let snippet = cx.sess().source_map().span_to_snippet(span).ok()?;