pre py2to3 step zero

pre2to3_step_zero.sh

#! /bin/sh
#
# * fix only print_function, absolute_import
# * keep the target as code working in Python 2.7
#

_2to3="${_2to3:-/c/Python35/Tools/scripts/2to3.py}"
#
test -d "$1" && exit 1  # must be file
test -f "$1" || exit 1  # must be file
test -f "$1".bak && exit 1  # must be fresh

#
(python "${_2to3}" -f print -f import -w "$1" 2>&1) > /dev/null || exit $?

#
pf=`grep "^from __future__ import print_function" "$1"`
ab=`grep "^from __future__ import absolute_import" "$1"`

#
sp=`sed '1,/^[^#].*$/!d' "$1" | sed '$d' | wc -l`
tmp=/tmp/"`basename $1`"
(
exec > "${tmp}"
sed "1,${sp}!d" "$1"
if test -z "${pf}" ; then
    echo "from __future__ import print_function"
fi
if test -z "${ab}" ; then
    echo "from __future__ import absolute_import"
fi
if test \( -z "${pf}" -o -z "${ab}" \) ; then
    echo
fi
sed "`expr ${sp} + 1`,\$!d" "$1"
) && mv -fv "$1" "$1".bak2 && mv -fv "${tmp}" "$1" && diff -u "$1".bak "$1"