DEFAULT NOW() WITH TIME ZONE 'UTC' is getting ignored, thus returning a naive datetime when queried.

还没有人认领这个 Issue。

* **asyncpg version**: 0.27.0
* **PostgreSQL version**: 15.1
* **Do you use a PostgreSQL SaaS? If so, which? Can you reproduce
the issue with a local PostgreSQL install?**: No
* **Python version**: 3.11.1 and 3.10.1
* **Platform**: Windows 11 or PC
* **Do you use pgbouncer?**: No
* **Did you install asyncpg with pip?**: Yes
* **If you built asyncpg locally, which version of Cython did you use?**: No
* **Can the issue be reproduced under both asyncio and
[uvloop](https://github.com/magicstack/uvloop)?**: Probably, never tried.

`DEFAULT NOW() WITH TIME ZONE 'UTC'` is not getting parsed to `datetime.datetime` with `tzinfo`. It basically ignores the `tzinfo` and returns a naive datetime when queried. Inserting an aware datetime is fine though.

使用带有 DEFAULT NOW() WITH TIME ZONE 'UTC' 的列，通过 asyncpg 0.27.0、PostgreSQL 15.1 和 Python 3.10 或 3.11 重现该报告。首先跟踪返回的值是如何转换为 datetime 的，然后验证查询结果保留了 tzinfo，同时 aware datetime 的插入仍能正常工作。

由索引模型根据 Issue 内容生成。