* 用例1：查询特定日期的可转债列表
```
import dai
df = dai.query("""
SELECT
date, instrument, name
FROM cn_cbond_instruments""",
filters={"date": ["2023-06-01"]}
).df()
```
* 用例2：查询特定可转债的信息
```
import dai
df = dai.query("""
SELECT
date, instrument, name
FROM cn_cbond_instruments
WHERE name LIKE '%22转债%'
ORDER BY date""",
filters={"date": ["2023-01-01", "2023-12-31"]}
).df()
```