{"load_density": [
  ["LD_register_variables", {"variables": {"base": "https://httpbin.org"}}],
  ["LD_start_test", {
    "user_detail_dict": {"user": "fast_http_user"},
    "user_count": 30,
    "spawn_rate": 10,
    "test_time": 30,
    "tasks": {
      "mode": "weighted",
      "tasks": [
        {"method": "get", "request_url": "${var.base}/get",   "weight": 7,
         "name": "browse"},
        {"method": "get", "request_url": "${var.base}/delay/1", "weight": 1,
         "name": "expensive"}
      ]
    }
  }],
  ["LD_generate_summary_report", {"report_name": "weighted_mix"}]
]}