Uses wrong python binary for bytecompile?

[jflemer-ndp]

I'm not 100% sure this is a bug or not. I ran into it because I did not have the specific xxx-build RPM installed (rh-python35-build) to override some of the generic SCL macros, but look at this line:
https://github.com/sclorg/scl-utils/blob/master/rpm/brp-scl-python-bytecompile#L42
It ended up trying to use /usr/bin/python3.5 which does not exist.

I think it might make more sense to use:

python_binary=$scl_path/usr/bin/$(basename $python_libdir)

Or:

if [ -e $scl_path/usr/bin/$(basename $python_libdir) ]; then
  python_binary=$scl_path/usr/bin/$(basename $python_libdir)
else
  python_binary=/usr/bin/$(basename $python_libdir)
fi

(Or the entire loop could be refactored to be

for path_prefix in "" $scl_path; do
  python_bin=$path_prefix/usr/bin/$(basename $python_libdir)
  for python_libdir in $RPM_BUILD_ROOT/$path_prefix/usr/lib{,64}/python[0-9].[0-9]/; do
    ...
  done
done

)