• smtpd, server side module
• smtplib, client side module

#server.py
import smtpd
import asyncore

class CustomSMTPServer(smtpd.SMTPServer):
    
    def process_message(self, peer, mailfrom, rcpttos, data):
        print 'Receiving message from:', peer
        print 'Message addressed from:', mailfrom
        print 'Message addressed to  :', rcpttos
        print 'Message length        :', len(data)
        return

server = CustomSMTPServer(('127.0.0.1', 1025), None)

asyncore.loop()
			

#client.py
import smtplib
import email.utils
from email.mime.text import MIMEText

# Create the message
msg = MIMEText('This is the body of the message.')
msg['Subject'] = 'Simple test message'

server = smtplib.SMTP('127.0.0.1', 1025)
server.set_debuglevel(True) # show communication with the server
try:
    server.sendmail('eagletiger1@gmail.com', ['lchen@ecsu.edu', 'lchen@cs.odu.edu'], msg.as_string())
finally:
    server.quit()
			

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