Patch by Jim Fulton.

in case of embedded null characters/bytes.  Patch by Xiang Zhang.

in case of embedded null characters/bytes.  Patch by Xiang Zhang.

and point users to developers guide.

Patch by Nathan Harold.

concatenations.  Patch by Xiang Zhang.

concatenations.  Patch by Xiang Zhang.

Make the default key set depend on the platform.
Add tests for changes to the config module.

This backports the fix from #16611, per discussion with the release
manager.

Patch by Jaysinh Shukla.

Android build.

http.cookie.time2netscape, confirming the netscape cookie format.

confirming the netscape cookie format.

bytearray for integers in and out of the Py_ssize_t range.
Patch by Xiang Zhang.

as 'ANDROID_API_LEVEL'.