preprocess_intcode.py

import sys
import re

x = re.compile('(\S+):')

s = open(sys.argv[1],'r').readlines()
s = [x.strip() for x in s]
s = [x for x in s if x[:2] != '//' and x != '']

cmds = []
tags = {}
for r in s:
    m = x.match(r)
    if m is not None:
        tags[m.groups()[0]] = len(cmds)
    else:
        cmds.extend([x for x in r.split(',') if x != ''])

cmds = [tags.get(x) if x in tags else int(x) for x in cmds]
print(','.join([str(x) for x in cmds]))