请提供一份关于城市交通拥堵的数据分析报告，请以JSON格式输出，并且每个数据点包含日期、地点和交通拥堵指数。
user
{
  "report": {
    "title": "城市交通拥堵数据分析报告",
    "data": [
      {"date": "2023-10-01", "location": "市中心", "congestion_index": 85},
      {"date": "2023-10-02", "location": "市中心", "congestion_index": 78},
      {"date": "2023-10-03", "location": "市中心", "congestion_index": 91},
      {"date": "2023-10-01", "location": "城东区", "congestion_index": 60},
      {"date": "2023-10-02", "location": "城东区", "congestion_index": 65},
      {"date": "2023-10-03", "location": "城东区", "congestion_index": 70}
    ]
  }
}
assistant