import smtplib
smtpserver = smtplib.SMTP("mailhub.corpex-net.de",25)
#smtpserver.connect()
header = 'To:' + toAdr + '\n' + 'From:' + fromAdr + '\n' + 'Subject: ' + mailSubject +'\n'
msg = header + '\n' + msgText
smtpserver.sendmail(fromAdr, toAdr, msg) # toAdr kann auch eine Liste sein
smtpserver.quit()

Doku https://docs.python.org/2/library/smtplib.html