As the one who opened the ticket, I only intended that the ticket fix whatever was causing the stack to create camera.py with the restrictive permissions. In the individual case of "my" shared stack, I had enough access to change the permissions of camera.py myself by hand (if that is what Tim Jenness is asking).

Ok. I was confused as to whether the files in question were committed to the repo with the wrong permissions or created at build time with the wrong permissions.

See my first comment above: the files are now created at build-time. I'm guessing in the past (when they had been checked in), someone had manually fixed the permissions after building them.

Two comments in review, the main one being whether we should make this a function (in lsst.utils?) since we might want this elsewhere and it's not obviously straightforward (agreed about the sadness of python's umask interface).

The patch was reworked to chmod the source tempfile before being renamed and to use shutil.move in place of os.rename.

It is probably worth doing a search of pypi for a module that 'improves' upon the tempfile interface before we add a wrapper method.