Split library into two parts: DB-API 2.0 compatible and Asyncio style

I am very interested in using this library since type support in psycopg2 is awful to work with. However, some projects still use Python 2.7, and will for another 4 years. Would it be possible to split asyncpg into two parts, one with an asynchronous API, usable with Python 3.5 and above, and one synchronous API that can be compatible across both 2.7 and 3.5 and above?

My proposal is a DB-API 2.0 (PEP 249) compatible API that can be utilized by the asyncio part of the library. The benefits is that applications that do not need asynchronous calls can use the same underlying library as those who do. With this code that doesn't rely on co-routines can use the type support provided by asyncpg.

I haven't used this project yet, or dived into its internals, and don't know whether it is feasible at all to do this. I am just venting my ideas.

该 issue 没有列出实现文件或测试。首先检查 asyncpg 现有的 asyncio API，并将提议的同步 DB-API 2.0 接口与 PEP 249 以及 Python 2.7 兼容性进行比较。由于这是一项探索性的架构提议，维护者首先需要确定可行性、范围和可衡量的完成状态。