abuild@greinerT450s:~> rpmbuild -vv -ba --define '_srcdefattr (-,root,root)' --nosignature --define '_build_create_debug 1' /home/abuild/rpmbuild/SOURCES/python-Cython.spec
ufdio:       1 reads,    19451 total bytes in 0.000017 secs
ufdio:       1 reads,     2823 total bytes in 0.000005 secs
sh: /usr/bin/python2: No such file or directory
ufdio:       1 reads,       13 total bytes in 0.000002 secs
ufdio:       1 reads,       13 total bytes in 0.000004 secs
error: lua script failed: [string "<lua>"]:9: invalid use of '%' in replacement string
D:   1<   D: echo python36 > _current_flavor D: 
D:   0< D: 
python_flavor=`[ -f _current_flavor ] && cat _current_flavor || true` 
if [ -z "$python_flavor" ]; then python_flavor="tmp"; fi 
if [ "$python_flavor" != "python36" ]; then 
    if [ -d build ]; then mv build _build.$python_flavor; fi 
    if [ -d _build.python36 ]; then mv _build.python36 build; fi 
fi 
echo python36 > _current_flavor D: 
ufdio:       1 reads,    19451 total bytes in 0.000004 secs
ufdio:       1 reads,     2823 total bytes in 0.000001 secs

        cmd = cmd:gsub("$python%f[%s]", rpm.expand("%__" .. python))\
        -- when used as flavor expansion for a custom macro\
        cmd = cmd:gsub("$python", python)\
        print(rpm.expand(cmd .. "\\n"))\