Embedding python in bash script example

python_in_bash.sh

#/usr/bin/which sh
set -e

PRE_SOURCEFILE=$(mktemp)
$(which python) - "${0}" "${@}" "--source" "${PRE_SOURCEFILE}" "--prefix" "PRE" <<END
import argparse
import sys
import tempfile


sys.argv = sys.argv[1:]

common = argparse.ArgumentParser(add_help=False)
common.add_argument('--source', help=argparse.SUPPRESS)
common.add_argument('--prefix', help=argparse.SUPPRESS)

parser = argparse.ArgumentParser(description='BLAH BLAH BLAH '
                                             'BLAH BLAH BLAH')
subparsers = parser.add_subparsers(title='BLAH BLAH BLAH '
                                         'BLAH BLAH BLAH',
                                   dest='command', metavar='')

load = subparsers.add_parser('mod', parents=[common],
                             help='BLAH BLAH BLAH')

load.add_argument('dividend', type=int, help='dividend')
load.add_argument('divisor', type=int, help='divisor')

args = parser.parse_args()

with open(args.source, 'w') as f:
    for arg in vars(args):
        if arg in ['source', 'prefix']:
            continue
        val = getattr(args, arg)
        if isinstance(val, list):
            val = ','.join(val)
        f.write('%s_%s="%s"\n' % (args.prefix, arg.upper(), val))
END

if [[ -s ${PRE_SOURCEFILE} ]]
then
    source ${PRE_SOURCEFILE}
else
    exit 0
fi

echo $((${PRE_DIVIDEND}%${PRE_DIVISOR}))