Verify email box exists

test-email.py

#Verify email box exists
#Author: Bruno da Silva Valenga - <brunodasilvalenga.com.br>
#Created: 08/25/2014
#Usage: script.py [email protected]
#Install lib DNS: https://github.com/rthalley/dnspython

import socket, smtplib, re, sys, dns.resolver

addressToVerify = sys.argv[1]
match = re.match('^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,4})$', addressToVerify)

domain = addressToVerify.split("@")[1]

if match == None:
        print('Bad Syntax')
        raise ValueError('Bad Syntax')

records = dns.resolver.query(domain, 'MX')
mxRecord = records[0].exchange
mxRecord = str(mxRecord)

# Get local server hostname
host = socket.gethostname()

# SMTP lib setup (use debug level for full output)
server = smtplib.SMTP()
server.set_debuglevel(0)

# SMTP Conversation
server.connect(mxRecord)
server.helo(host)
server.mail(addressToVerify)
code, message = server.rcpt(str(addressToVerify))
server.quit()

# Assume 250 as Success
if code == 250:
        print('Success')
else:
        print('Bad')