fix: market-sync 2h timeout 截断 + 加 daily-check 巡检

work #01 (2026-07-03)：昨天 15:30 runall 中 kline_5min 全量 69min 把 2h
窗口吃满，share_snapshot / market_regime 被 systemd SIGTERM 截断；
今天又叠加 worker.py 未长驻，导致 10 个 task missed。

变更：
- bin/systemd/market-sync.service: TimeoutStartSec 7200 → 14400 (4h)
- bin/daily_sync_check.py: 新增每日巡检，读 PG dataset_registry，
  对比 SCHEDULE 判定 ok/missed/failed/stuck/never_run，写 JSON 报告，
  失败时 POST HMAC webhook
- bin/systemd/market-sync-daily-check.{service,timer}: 23:00 daily 触发
  daily_check（替代 session-only 的 /loop 方案）
- config/daily_check_secrets.env.template: webhook 配置模板
- docs/works/2026-07-03-01-market-sync-timeout.md: 完整 work 记录
  （根因 + 中期/长期改进建议）

Co-Authored-By: Claude <noreply@anthropic.com>

bin/daily_sync_check.py

@@ -0,0 +1,408 @@
+"""每日同步任务巡检。
+
+读 PG `dataset_registry`，对比今日预期调度窗口，给出每个 task 的健康状态，
+写 `logs/daily_check_YYYYMMDD_HHMMSS.json` 报告，仅在有失败/漏跑时 POST webhook。
+
+用法：
+  .venv/bin/python bin/daily_sync_check.py            # 默认检查"今天"
+  .venv/bin/python bin/daily_sync_check.py --dry-run  # 只生成报告，不 POST
+  .venv/bin/python bin/daily_sync_check.py --report-only  # 完全不读 secrets / 不 POST
+  .venv/bin/python bin/daily_sync_check.py --date 2026-07-02  # 检查指定日期
+
+为什么是 stand-alone（不放在 app.tasks 下）：
+  - 巡检逻辑独立于 sync 业务，混在 app.tasks 会让注册表臃肿
+  - 独立脚本便于 cron / systemd timer / /loop 三种触发方式共用
+"""
+from __future__ import annotations
+
+import argparse
+import hashlib
+import hmac
+import json
+import logging
+import os
+import re
+import sys
+import time
+from datetime import date, datetime, timedelta
+from pathlib import Path
+from typing import Any, Optional
+
+import requests
+
+
+# ── 路径与日志 ─────────────────────────────────────────────────────────────
+PROJECT_ROOT = Path(__file__).resolve().parent.parent
+if str(PROJECT_ROOT) not in sys.path:
+    sys.path.insert(0, str(PROJECT_ROOT))
+
+LOG_DIR = PROJECT_ROOT / "logs"
+SECRETS_FILE = PROJECT_ROOT / "config" / "daily_check_secrets.env"
+
+LOG = logging.getLogger("daily-sync-check")
+
+
+# ── 预期调度表 ─────────────────────────────────────────────────────────────
+# 与 [[market-data-overview]] 保持一致；同步触发点（HH:MM）按 Asia/Shanghai 解释。
+# weekend_only=True 表示只在周六/周日期望运行（实际仅 stock_node 周六一次）。
+SCHEDULE: dict[str, dict[str, Any]] = {
+    "stock_basic":     {"window_end": "09:30", "weekend_only": False},
+    "industry_sector": {"window_end": "09:45", "weekend_only": False},
+    "kline_index":     {"window_end": "15:35", "weekend_only": False},
+    "kline_daily":     {"window_end": "15:45", "weekend_only": False},
+    "kline_5min":      {"window_end": "16:05", "weekend_only": False},
+    "market_regime":   {"window_end": "16:20", "weekend_only": False},
+    "share_snapshot":  {"window_end": "16:25", "weekend_only": False},
+    "moneyflow":       {"window_end": "21:40", "weekend_only": False},
+    "longhubang":      {"window_end": "22:05", "weekend_only": False},
+    "stock_node":      {"window_end": "12:00", "weekend_only": True},   # 周六
+}
+
+
+# ── 状态判定 ───────────────────────────────────────────────────────────────
+def _parse_ts(s: Optional[str]) -> Optional[datetime]:
+    """dataset_registry 时间字段是 '%Y-%m-%d %H:%M:%S' 或 None。"""
+    if not s:
+        return None
+    for fmt in ("%Y-%m-%d %H:%M:%S", "%Y-%m-%dT%H:%M:%S", "%Y-%m-%dT%H:%M:%S%z"):
+        try:
+            return datetime.strptime(s, fmt)
+        except ValueError:
+            continue
+    return None
+
+
+def _classify_task(
+    row: dict[str, Any],
+    check_date: date,
+    now: datetime,
+) -> dict[str, Any]:
+    """判定单个 task 在 check_date 的健康状态。
+
+    返回字段：
+      status: ok | missed | failed | running | never_run | not_expected
+      reason: 简短中文原因
+      last_success_at / last_failure_at / last_error / needs_resync: 原值透传
+    """
+    dataset_id = row["dataset_id"]
+    enabled = (row.get("enabled") or 0) == 1
+    spec = SCHEDULE.get(dataset_id)
+    is_weekend = check_date.weekday() >= 5
+
+    if not enabled:
+        return {
+            "dataset_id": dataset_id,
+            "name": row.get("name", ""),
+            "status": "disabled",
+            "reason": "enabled=0",
+            "last_success_at": row.get("last_success_at"),
+            "last_failure_at": row.get("last_failure_at"),
+            "last_error": row.get("last_error"),
+            "needs_resync": row.get("needs_resync", 0),
+            "status_field": row.get("status", "idle"),
+        }
+
+    # weekend 期望判定
+    if spec and spec["weekend_only"] and not is_weekend:
+        return {
+            "dataset_id": dataset_id,
+            "name": row.get("name", ""),
+            "status": "not_expected",
+            "reason": "周末专属任务，今天不期望",
+            "last_success_at": row.get("last_success_at"),
+            "last_failure_at": row.get("last_failure_at"),
+            "last_error": row.get("last_error"),
+            "needs_resync": row.get("needs_resync", 0),
+            "status_field": row.get("status", "idle"),
+        }
+    if spec and not spec["weekend_only"] and is_weekend:
+        return {
+            "dataset_id": dataset_id,
+            "name": row.get("name", ""),
+            "status": "not_expected",
+            "reason": "周末不调度",
+            "last_success_at": row.get("last_success_at"),
+            "last_failure_at": row.get("last_failure_at"),
+            "last_error": row.get("last_error"),
+            "needs_resync": row.get("needs_resync", 0),
+            "status_field": row.get("status", "idle"),
+        }
+
+    last_success = _parse_ts(row.get("last_success_at"))
+    last_failure = _parse_ts(row.get("last_failure_at"))
+    status_field = row.get("status", "idle")
+
+    # 还在跑（卡死检测）
+    if status_field == "running":
+        started = _parse_ts(row.get("started_at"))
+        if started and (now - started) > timedelta(hours=2):
+            return {
+                "dataset_id": dataset_id,
+                "name": row.get("name", ""),
+                "status": "stuck",
+                "reason": f"running > 2h, started_at={row.get('started_at')}",
+                "last_success_at": row.get("last_success_at"),
+                "last_failure_at": row.get("last_failure_at"),
+                "last_error": row.get("last_error"),
+                "needs_resync": row.get("needs_resync", 0),
+                "status_field": status_field,
+            }
+        return {
+            "dataset_id": dataset_id,
+            "name": row.get("name", ""),
+            "status": "running",
+            "reason": f"status=running, started_at={row.get('started_at')}",
+            "last_success_at": row.get("last_success_at"),
+            "last_failure_at": row.get("last_failure_at"),
+            "last_error": row.get("last_error"),
+            "needs_resync": row.get("needs_resync", 0),
+            "status_field": status_field,
+        }
+
+    # 从未跑过
+    if last_success is None and last_failure is None:
+        return {
+            "dataset_id": dataset_id,
+            "name": row.get("name", ""),
+            "status": "never_run",
+            "reason": "从未同步过",
+            "last_success_at": row.get("last_success_at"),
+            "last_failure_at": row.get("last_failure_at"),
+            "last_error": row.get("last_error"),
+            "needs_resync": row.get("needs_resync", 0),
+            "status_field": status_field,
+        }
+
+    # 今日是否有成功？
+    today_start = datetime.combine(check_date, datetime.min.time())
+    if last_success and last_success >= today_start:
+        return {
+            "dataset_id": dataset_id,
+            "name": row.get("name", ""),
+            "status": "ok",
+            "reason": f"今日已成功 @ {last_success.strftime('%H:%M:%S')}",
+            "last_success_at": row.get("last_success_at"),
+            "last_failure_at": row.get("last_failure_at"),
+            "last_error": row.get("last_error"),
+            "needs_resync": row.get("needs_resync", 0),
+            "status_field": status_field,
+        }
+
+    # 今日失败过？
+    if last_failure and last_failure >= today_start and (
+        not last_success or last_failure > last_success
+    ):
+        return {
+            "dataset_id": dataset_id,
+            "name": row.get("name", ""),
+            "status": "failed",
+            "reason": f"今日失败 @ {last_failure.strftime('%H:%M:%S')}: "
+                      f"{(row.get('last_error') or '')[:120]}",
+            "last_success_at": row.get("last_success_at"),
+            "last_failure_at": row.get("last_failure_at"),
+            "last_error": row.get("last_error"),
+            "needs_resync": row.get("needs_resync", 0),
+            "status_field": status_field,
+        }
+
+    # 期望窗口已过但今日没成功
+    return {
+        "dataset_id": dataset_id,
+        "name": row.get("name", ""),
+        "status": "missed",
+        "reason": (
+            f"今日未成功（last_success={last_success.strftime('%Y-%m-%d %H:%M') if last_success else 'never'}）"
+        ),
+        "last_success_at": row.get("last_success_at"),
+        "last_failure_at": row.get("last_failure_at"),
+        "last_error": row.get("last_error"),
+        "needs_resync": row.get("needs_resync", 0),
+        "status_field": status_field,
+    }
+
+
+# ── 报告生成 ───────────────────────────────────────────────────────────────
+def build_report(check_date: date) -> dict[str, Any]:
+    """生成当日巡检报告。"""
+    from app.core.db import ops as db_ops  # 延迟导入:避免单独跑这个脚本时加载 .env
+
+    now = datetime.now()
+    rows = db_ops.fetch_dataset_registry_rows()
+    classified = [_classify_task(r, check_date, now) for r in rows]
+
+    # 汇总计数
+    counts: dict[str, int] = {}
+    for c in classified:
+        counts[c["status"]] = counts.get(c["status"], 0) + 1
+
+    # 告警列表：只挑非 ok / non-expected 的
+    alerts = [
+        {"dataset_id": c["dataset_id"], "status": c["status"], "reason": c["reason"]}
+        for c in classified
+        if c["status"] in {"missed", "failed", "stuck", "never_run"}
+    ]
+
+    overall = "ok" if not alerts else (
+        "warning" if any(a["status"] in {"missed", "never_run"} for a in alerts) else "error"
+    )
+
+    return {
+        "schema_version": 1,
+        "generated_at": now.strftime("%Y-%m-%d %H:%M:%S"),
+        "check_date": check_date.isoformat(),
+        "overall": overall,
+        "counts": counts,
+        "alerts": alerts,
+        "tasks": classified,
+    }
+
+
+def write_report(report: dict[str, Any]) -> Path:
+    """把报告写到 logs/daily_check_YYYYMMDD_HHMMSS.json。"""
+    LOG_DIR.mkdir(parents=True, exist_ok=True)
+    ts = datetime.now().strftime("%Y%m%d_%H%M%S")
+    path = LOG_DIR / f"daily_check_{ts}.json"
+    path.write_text(json.dumps(report, ensure_ascii=False, indent=2), encoding="utf-8")
+    return path
+
+
+def print_summary(report: dict[str, Any]) -> None:
+    """stdout 一眼看懂的汇总。"""
+    print("=" * 78)
+    print(f"每日同步巡检  date={report['check_date']}  overall={report['overall']}")
+    print("=" * 78)
+    print(f"counts: {report['counts']}")
+    if report["alerts"]:
+        print(f"\n告警 ({len(report['alerts'])}):")
+        for a in report["alerts"]:
+            print(f"  - [{a['status']:>9}] {a['dataset_id']:<20} {a['reason']}")
+    else:
+        print("\n✅ 所有任务今日已成功")
+    # 完整列表
+    print(f"\n全部 {len(report['tasks'])} 个任务:")
+    for t in report["tasks"]:
+        icon = {
+            "ok": "✅",
+            "missed": "❌",
+            "failed": "❌",
+            "stuck": "⚠️",
+            "running": "🔄",
+            "never_run": "❓",
+            "not_expected": "⏸ ",
+            "disabled": "🚫",
+        }.get(t["status"], "·")
+        print(f"  {icon} [{t['status']:>13}] {t['dataset_id']:<20} {t['reason']}")
+
+
+# ── Webhook ────────────────────────────────────────────────────────────────
+SIG_HEADER_CANDIDATES: list[tuple[str, str]] = [
+    ("X-Hub-Signature-256", "sha256={sig}"),
+    ("X-Webhook-Signature", "{sig}"),
+    ("X-Gitlab-Token", "{secret}"),
+]
+HTTP_TIMEOUT = 10
+
+
+def _load_secrets() -> dict[str, str]:
+    out: dict[str, str] = {}
+    if not SECRETS_FILE.exists():
+        return out
+    try:
+        for raw in SECRETS_FILE.read_text(encoding="utf-8").splitlines():
+            line = raw.strip()
+            if not line or line.startswith("#"):
+                continue
+            if "=" not in line:
+                continue
+            k, v = line.split("=", 1)
+            k = k.strip()
+            v = v.strip().strip('"').strip("'")
+            if k and v:
+                out[k] = v
+    except Exception as e:
+        LOG.error("failed to parse %s: %s", SECRETS_FILE, e)
+    return out
+
+
+def post_webhook(url: str, secret: str, payload: dict[str, Any], *, dry_run: bool = False) -> int:
+    body = json.dumps(payload, ensure_ascii=False).encode("utf-8")
+    sig = hmac.new(secret.encode("utf-8"), body, hashlib.sha256).hexdigest()
+
+    if dry_run:
+        print(f"[webhook DRY-RUN] {url}")
+        print(json.dumps(payload, ensure_ascii=False, indent=2))
+        return 200
+
+    for hdr_name, value_fmt in SIG_HEADER_CANDIDATES:
+        sig_value = value_fmt.format(sig=sig, secret=secret)
+        headers = {"Content-Type": "application/json", hdr_name: sig_value}
+        try:
+            r = requests.post(url, data=body, headers=headers, timeout=HTTP_TIMEOUT)
+            if r.status_code in (401, 403):
+                LOG.info("auth header %s rejected (%s) — trying next", hdr_name, r.status_code)
+                continue
+            return r.status_code
+        except requests.RequestException as e:
+            LOG.error("POST %s failed with %s: %s", url, hdr_name, e)
+            return 0
+    return 0
+
+
+def maybe_alert(report: dict[str, Any], secrets: dict[str, str], *, dry_run: bool) -> None:
+    """只在 overall != ok 时 POST。"""
+    if report["overall"] == "ok":
+        LOG.info("全部 ok，跳过 webhook")
+        return
+
+    url = secrets.get("FAILURE_WEBHOOK_URL")
+    secret = secrets.get("FAILURE_WEBHOOK_SECRET")
+    if not url or not secret:
+        LOG.warning("FAILURE_WEBHOOK_URL/SECRET 未配置，跳过 POST")
+        return
+
+    payload = {
+        "task": "daily_check",
+        "service": "bin/daily_sync_check.py",
+        "status": report["overall"],
+        "check_date": report["check_date"],
+        "counts": report["counts"],
+        "alerts": report["alerts"],
+        "generated_at": report["generated_at"],
+    }
+    status = post_webhook(url, secret, payload, dry_run=dry_run)
+    LOG.info("webhook POST → %s", status)
+
+
+# ── CLI ────────────────────────────────────────────────────────────────────
+def main(argv: Optional[list] = None) -> int:
+    parser = argparse.ArgumentParser(description="每日同步巡检")
+    parser.add_argument("--date", help="检查日期 YYYY-MM-DD（默认今天）")
+    parser.add_argument("--dry-run", action="store_true", help="webhook 走 dry-run（仍写报告）")
+    parser.add_argument("--report-only", action="store_true", help="不读 secrets、不 POST")
+    args = parser.parse_args(argv)
+
+    logging.basicConfig(
+        level=logging.INFO,
+        format="%(asctime)s %(levelname)-7s %(name)s: %(message)s",
+        datefmt="%Y-%m-%dT%H:%M:%S",
+    )
+
+    if args.date:
+        check_date = datetime.strptime(args.date, "%Y-%m-%d").date()
+    else:
+        check_date = date.today()
+
+    report = build_report(check_date)
+    path = write_report(report)
+    print_summary(report)
+    LOG.info("报告已写: %s", path)
+
+    if not args.report_only:
+        secrets = _load_secrets()
+        maybe_alert(report, secrets, dry_run=args.dry_run)
+
+    return 0 if report["overall"] == "ok" else 1
+
+
+if __name__ == "__main__":
+    sys.exit(main())

bin/systemd/market-sync-daily-check.service

@@ -0,0 +1,31 @@
+[Unit]
+Description=Market sync daily check — reads dataset_registry, writes report, alerts on failures
+Documentation=file:///home/gao/Development/quant_home/market_sync/bin/daily_sync_check.py
+After=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=oneshot
+WorkingDirectory=/home/gao/Development/quant_home/market_sync
+User=gao
+Group=gao
+
+# 巡检：读 PG dataset_registry，对比今日预期，写 logs/daily_check_*.json
+# 失败时 POST webhook 到 FAILURE_WEBHOOK_URL（HMAC-SHA256 签名）
+ExecStart=/home/gao/Development/quant_home/market_sync/.venv/bin/python /home/gao/Development/quant_home/market_sync/bin/daily_sync_check.py
+
+# 巡检应 < 30s 完成；超时 = PG 不通或代码 bug，不让卡死
+TimeoutStartSec=120
+
+# 不要 Restart=（oneshot 失败就让 OnFailure= 发通知，别自动重跑）
+# 失败时 exit code = 1，可被 OnFailure= 钩住发通知
+
+# 日志走 journald（journalctl -u market-sync-daily-check -f）
+StandardOutput=journal
+StandardError=journal
+SyslogIdentifier=market-sync-daily-check
+
+Environment=PYTHONUNBUFFERED=1
+
+[Install]
+WantedBy=multi-user.target

bin/systemd/market-sync-daily-check.timer

@@ -0,0 +1,15 @@
+[Unit]
+Description=Schedule market sync daily check — Daily 23:00 Asia/Shanghai
+# market-sync-daily-check.service 是这个 timer 的执行单元
+# 23:00 触发：周一~五最后一个任务是 longhubang @ 22:00，留 1h buffer；
+# 周六 23:00 给 stock_node @ 11:30 留 11h+ buffer
+
+[Timer]
+# 每天 23:00 触发；Persistent=true 确保关机/错过时下次开机补跑
+OnCalendar=*-*-* 23:00:00 Asia/Shanghai
+Persistent=true
+Unit=market-sync-daily-check.service
+# 不要 AccuracySec（默认 1min 漂移够用）
+
+[Install]
+WantedBy=timers.target

bin/systemd/market-sync.service

@@ -13,8 +13,10 @@ Group=gao
 # 入口脚本（runall_once.py + structured_watch.sh 二合一）
 ExecStart=/home/gao/Development/quant_home/market_sync/bin/market_sync_run.sh
 
-# 硬上限 2h（实际 ~80min，留 buffer 给 retry / 慢任务）
+# 硬上限 4h（实际 ~80min + kline_5min 增量 70min, 总 ~2.5h, 留 buffer 给 retry / 慢任务）
-TimeoutStartSec=7200
+# 历史 bug（2026-07-02）：2h 超时截断，share_snapshot / market_regime 没跑成
+# 详见 docs/works/2026-07-03-01-market-sync-timeout.md
+TimeoutStartSec=14400
 
 # 不要 Restart=（oneshot 失败就让 OnFailure= 发通知，别自动重跑——
 # 重跑会撞外部 API 限流窗口，浪费 1.5h）

config/daily_check_secrets.env.template

@@ -0,0 +1,6 @@
+# 每日巡检 webhook 配置（HMAC-SHA256 签名）
+# 复制为 daily_check_secrets.env 后填入真实值，文件权限 600
+
+# 失败 / 漏跑时调用（必填，否则只在本地报告）
+FAILURE_WEBHOOK_URL=
+FAILURE_WEBHOOK_SECRET=

docs/works/2026-07-03-01-market-sync-timeout.md

@@ -0,0 +1,78 @@
+# 2026-07-03 — work #01: market-sync.service 2h timeout 截断同步
+
+## 发现
+
+跑 `bin/daily_sync_check.py --report-only`（周五 10:31）→ 10 个 missed：
+
+```
+❌ stock_basic / kline_daily / kline_index / kline_5min / tick_trade
+❌ moneyflow / industry_sector / sector_features / market_regime / longhubang
+✅ share_snapshot    (今日 00:03:01 手动跑过)
+⏸  stock_node        (周末专属任务，今天周五不期望)
+```
+
+## 根因
+
+不是今天调度出问题，是**昨天 2026-07-02 15:30 runall 没跑完**：
+
+```
+15:30:01 启动 runall
+15:38:50 stock_basic 完成      (529s)
+15:38:58 kline_index 完成       (2s)
+15:56:54 kline_daily 完成      (1072s)   warning
+17:06:09 kline_5min 完成       (4150s=69min)  ← 单 task 吃掉一半窗口
+17:22:37 industry_sector 完成   (983s)   warning (baostock timeout)
+17:24:27 sector_features 完成   (105s)
+17:24:32 >>> 开始 share_snapshot
+17:30:01 systemd SIGTERM 杀进程  ← TimeoutStartSec=7200 (2h) 到期
+✗ share_snapshot 没跑
+✗ market_regime 没跑
+```
+
+后果链：
+1. 昨天 kline_5min 全量同步 5207 只耗时 69 min（4150s），单 task 吃掉 1/2 窗口
+2. industry_sector 又因 baostock connection timed out 浪费 16 min
+3. 17:30 systemd timeout 砍掉 share_snapshot + market_regime
+4. 今天 09:00 该跑的 stock_basic 没跑 —— 因为 worker.py 没长驻 + market-sync.timer 只在 15:30 触发
+5. tick/moneyflow/lhb 几个独立 timer 在 21:05/21:35/22:00 跑过但今天又没补
+
+## 解决
+
+### 短期（本次 commit）
+
+- `bin/systemd/market-sync.service`: `TimeoutStartSec` 从 `7200` (2h) 提到 `14400` (4h)
+  - 注释 `实际 ~80min` → 改成 `~80min + kline_5min 增量 70min, 总 ~2.5h, 留 buffer`
+- 加 `bin/systemd/market-sync-daily-check.timer` + `.service`
+  - 每天 23:00 跑 `bin/daily_sync_check.py`，替代 `/loop` 方案的 session-only 限制
+
+### 中期（不在本次 commit，记录备查）
+
+- kline_5min 改成增量模式（当前是全量 5207 只每次），预计从 69min 降到 5min
+  - 增量条件：`bar_time >= 上次同步时间 - 1 天`（含补漏）
+- worker.py 长驻 + 进程内 scheduler 接管盘后 task 调度，与 systemd timer 二选一（[[dual-scheduler-overlap]]）
+- 失败 task 自动 retry 一次（仅 failed，不 retry partial-success / warning）
+
+### 长期（架构改进）
+
+- runall 拆成 fast-path / slow-path 两个 service：
+  - fast-path: stock_basic / kline_index / kline_daily / industry_sector / share_snapshot / market_regime（~30min）
+  - slow-path: kline_5min 全量（独立 timer @ 周日凌晨，避免挤占交易日窗口）
+
+## 关联
+
+- [[background-watcher-pitfalls]]: "不要让 systemd TimeoutStartSec= 自动收尾"
+  - 实际情况是 runall 卡在 kline_5min，wrapper 的 fast-poll 也没起到作用（runall 在 2h 内确实没退出，systemd 超时是对的）
+- [[dual-scheduler-overlap]]: worker.py 没运行 → 完全依赖 systemd timer
+- [[market-data-overview]]: 任务耗时分布
+
+## 验收
+
+commit 后验证：
+```bash
+sudo cp bin/systemd/market-sync.service /etc/systemd/system/
+sudo cp bin/systemd/market-sync-daily-check.{service,timer} /etc/systemd/system/
+sudo systemctl daemon-reload
+sudo systemctl restart market-sync.timer
+systemctl status market-sync-daily-check.timer
+# 等今晚 23:00 看 daily_check 报告
+```