Email Verifier

import re
import dns.resolver
import socket
import smtplib



def matcher(address):
    addressToVerify = address
    match = re.match('^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,4})$', addressToVerify)

    if match == None:
        return False
    if match:
        return True

address = str(input('Email Address: '))

if matcher(address) == True:
    regexp = re.search("\@(.*)", address)
    domain = regexp.group(1)
    print("Domain: %s "% domain)
    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(address)
    code, message = server.rcpt(str(address))
    server.quit()

    # Assume 250 as Success
    if code == 250:
        print('%s == Success'% address)
    else:
        print('%s == Bad'% address)
else:
    print("No Match")