{"ast_node_type":"other","tokens":[{"end":59,"kind":"keyword","start":0,"text":"LangItem::AsyncFn"}]}
            LangItem::AsyncFn => Some(ty::ClosureKind::Fn),
        match self.as_lang_item(id)? {
            LangItem::AsyncFnMut => Some(ty::ClosureKind::FnMut),