Packages that fail looking for /usr/bin/python(2)

[nieder]

On 13.0 (and 12 since 12.3) /usr/bin/python no longer exists. Only /usr/bin/python3 is provided by Xcode (or CLT). This is a list of packages that are reported to fail looking for /usr/bin/python(2) during configure or some other part of the build (items struck through were false reports):

- [ ] a2ps @wgscott

• asciidoc Update asciidoc to changed upstream source and build for python2.7 + python3 #946 (currently more broken for python2)
  - [ ] auctex
• ca-certificates Patches/updates for building with python3 on 12.0+ #945
  - [ ] cernlib2006
• cufflinks
  - [ ] djvulibre
  - [ ] djview @nieder
• docutils-py27 in Failed: phase installing: docutils-py27-0.14-1 failed #968
• doxygen Patches/updates for building with python3 on 12.0+ #945
• doxygen-doc 147eb78
• glib2-shlibs Patches/updates for building with python3 on 12.0+ #945
• gtk-doc (hardcodes python in %p/bin/gtkdoc-depscan) Patches/updates for building with python3 on 12.0+ #945
  - [ ] gv
  - [ ] imagemagick @nieder
• ledger @jessealama
• libglade @dmacks
• libnss3 @dmacks
• libnss3.0e @dmacks
  - [ ] lynx
  - [ ] mutt
• ninja Ninja looks for python #932, Enable python3 for ninja bootstrap on macOS 11+ #936
• qt5-qtdeclarative
• qt5-qtwebengine @nieder Patches/updates for building with python3 on 12.0+ #945
• qt5-qtwebkit
• scons Patches/updates for building with python3 on 12.0+ #945
• texlive
• youtube-dl
• zziplib duplicate(?) in Patches/updates for building with python3 on 12.0+ #945 (updating to latest breaks Shlibs compatibility)

[nieder]

These are possible fixes to packages so that they can find a working python (there are other solutions):

if [ -x /usr/bin/python ]; then
	export PYTHON=/usr/bin/python
else
	export PYTHON=/usr/bin/python3
fi

[ -x /usr/bin/python ] || pyversion=3
PYTHON=/usr/bin/python$pyversion

if [ -x /usr/bin/python ]; then
	./configure.py <FLAGS, ETC>
else
	/usr/bin/python3 ./configure.py <FLAGS, ETC>
fi