{"ast_node_type":"variable","tokens":[{"end":67,"kind":"keyword","start":0,"text":"let"}]}
        let LevelAndSource { level: old_level, src: old_src, .. } =
    fn insert_spec(&mut self, id: LintId, LevelAndSource { level, lint_id, src }: LevelAndSource) {
            self.provider.get_lint_level(id.lint, self.sess);