I imagine lots of other python REs fail if this one is failing ? :

$ cat test.py

import os
import sys
import re

pat = r'''d.........   # It is a directory.
          \+?          # It may have ACLs.
          \s+\d+       # It has some number of links.
          [^/]*        # Skip user, group, size, and date.
          /\.          # and end with the name of the file.
       '''
str = 'drwxr-xr-x. 25 root root 4096 Apr 20 15:28 /.'
if re.match(pat, str, re.VERBOSE) :
   print "MATCHED\n"
else :
   print "DID NOT MATCH"

$ LD_LIBRARY_PATH=`pwd` LD_PRELINK=`pwd`/libpython2.7.so.1.0 ./python ./test.py
DID NOT MATCH