p.py

#!/usr/bin/env python

import re


good = 'abc'
bad = 'ab\x00c'
#$rgx = '/^[\x00-\x20\x22\x2F\x3A\x3C\x3E\x5C]{1,'.strlen($tistr).'};/';


rgx = r'[\x00-\x20\x22\x2F\x3A\x3C\x3E\x5C]'

RE = re.compile(rgx)

print RE.search(good)
print RE.search(bad)