Message 68170 - Python tracker

OK, I think I got is now. The difference is between debug and release
builds.

Explanation:
- in release build, "import nul" calls stat("nul.pyd") which succeeds.
It then tries LoadLibrary("nul.pyd"), which fails with a DLL error.
- in debug builds, "import nul" first tries stat("nul_d.pyd") which
fails. It then tries stat("nul.py"), which succeeds to return an empty file!

Whaaaa.