{"ast_node_type":"variable","tokens":[{"end":90,"kind":"keyword","start":0,"text":"let"}]}
    let result = qcx.start_query(job_id, query.depth_limit(), || query.compute(qcx, key));
    let prof_timer = qcx.dep_context().profiler().query_provider();
    let dep_node_index = qcx.dep_context().dep_graph().next_virtual_depnode_index();