Generate crypt ( passwd compliant ) sha512 password with python

generate_sha512_passwd

#!/usr/bin/env python

import crypt
import string
import random
import sys
from optparse import OptionParser

def salt_generator(size=20, chars=string.ascii_uppercase + string.digits):
  return ''.join(random.choice(chars) for x in range(size))

usage = "usage: %prog [options] arg1 arg2"

parser = OptionParser(usage=usage)
parser.add_option("-p", "--password", dest="passwd",
                  help="Password to encrypt", metavar="<password>")
parser.add_option("-s", "--salt", dest="salt",
                  help="salt to use ( if not specified it's generated", metavar="<salt>")

(options,args) = parser.parse_args()

if not options.passwd:
  parser.error('No password given')

if not options.salt:
  options.salt = salt_generator()

print crypt.crypt(options.passwd, "$6$%s" % options.salt)