{"ast_node_type":"variable","tokens":[{"end":83,"kind":"keyword","start":0,"text":"let"}]}
                let old_str = &parent_str[old_range - parent.text_range().start()];
                let pre_str = &parent_str[pre_range - parent.text_range().start()];
                let post_str = &parent_str[post_range - parent.text_range().start()];