Example of pycrypto CCM mode

gcm.py

from Crypto.Cipher import AES
from Crypto.Random import get_random_bytes

hdr = b'To your eyes only'
plaintext = b'Attack at dawn'
key = b'Sixteen byte key'
nonce = get_random_bytes(11)
cipher = AES.new(key, AES.MODE_CCM, nonce)
cipher.update(hdr)
msg = nonce, hdr, cipher.encrypt(plaintext), cipher.digest()

# We assume that the tuple ``msg`` is transmitted to the receiver:

nonce, hdr, ciphertext, mac = msg
key = b'Sixteen byte key'
cipher = AES.new(key, AES.MODE_CCM, nonce)
cipher.update(hdr)
plaintext = cipher.decrypt(ciphertext)
try:
    cipher.verify(mac)
    print "The message is authentic: hdr=%s, pt=%s" % (hdr, plaintext)
except ValueError:
    print "Key incorrect or message corrupted"

MODE_CCM is supported by the dropin replacement of the original PyCrypto
https://github.com/Legrandin/pycryptodome