FYI, I'm maintaining a rebased version on my fork:

https://github.com/erlend-aasland/cpython/tree/sqlite-blob

Here's the changes I've applied upon PR 271:

- Use Argument Clinic
- Convert to heap types
- Adopt new CPython C APIs (Py_NewRef, Py_Is*, new slice API, etc.)
- Lint code (PEP 7, use CPython idioms, normalise variable and helper namings)
- Lint docs
- Normalise error messages
- Refactor very large functions, apply simplifications, and remove unneeded code
- Expand test suite to increase code coverage

I don't think it is ready for inclusion yet; the test suite needs to be restructured, or maybe rewritten from scratch. Pr. now most of the tests maintain a single connection with a prepared database. IMO, it's a fragile design and it is hard to read, debug, and verify the test code. I'll see if I can get to it in a couple of weeks.