pgp key notification script

#!/usr/bin/python
import fileinput
import re
import subprocess

contents = ""
for line in fileinput.input():
    contents = contents + line

from_address = re.match('(From )([^\s]+) ', contents).group(2)

p = subprocess.Popen(['gpg2','--decrypt'], stdin=subprocess.PIPE, stderr=subprocess.PIPE)
p.stdin.write(contents)
gpg_err = p.communicate()[1]
p.stdin.close()

reply = """-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

<begin canned response>

Hello!

It looks like you've sent me an email encrypted to my old PGP key.  Please be informed that I have a new key.  Follow the below instructions to use it:

Command Line:

    gpg2 --recv-keys 977A04EC512A9D0DB4A56E0ECDCAE8ED6842C592
    gpg2 --delete-keys 3CCDBB7355D1758F549354D20B123309D3366755

OSX (I think this works):

    Go into your GPG Keychain app, right-click and delete my key.  Then, download the new key from here:
    https://www.eff.org/files/2015/06/06/6842c592.txt
    Save it as a .pgp file on your desktop, and drag it into to your GPG Keychain app window.

Thanks!
Bill

<end canned response>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2

iQEcBAEBAgAGBQJW/ZV7AAoJEAsSMwnTNmdVYD0H/ip24it5Y8ZejPgPYBoYpYHJ
7/nxIvSeiVsCGaxJCjJ3jWjCsA6QuEVQhzZFRPNALZKb22D0WNQ0dGtGo1oKl0s7
GTUNTda5bsyJ19IxJgfdqD41aNbFGCdJAMfdnaW9luHid3LAzjfqdEhaKHB/Ik7s
VNb8XYtR8z+fnZ0H8Nk/yE/u//Gq399m1G9+ZDYmf28uDGIHSin1G1PqAaatgBgX
AwG6wr6WbNNSThw9nz7Ensa+zIdxh6xr2f/RczvE0+ZC8YF2dalPmvNWvJmdFj8b
OaT09okeV6iqOc0yTmuQCjqaxofP+e1M9n+aDdCUGn4YV2C3Ijilg3jI3jiR46U=
=n6va
-----END PGP SIGNATURE-----
"""

if re.search("encrypted with RSA key, ID 130933BE", gpg_err):
    if not re.search("encrypted with RSA key, ID E1368FB5", gpg_err):
        p = subprocess.Popen("mail -s 'Please use my new PGP key' " + from_address, shell=True, stdin=subprocess.PIPE)
        p.stdin.write(reply)
        p.stdin.close()