The smtplib Module

The smtplib module defines an SMTP client session object that can be used to send mail to any Internet machine with an SMTP or ESMTP listener daemon.

import smtplib

server = "smtp.gmail.com"
port = 587
username = "username"
password = "password"

sender = "me@domain"
recipient = "you@domain"
subject = "Python Email Test"
message = "Hello from Python!"

try:
    smtp = smtplib.SMTP(server, port)
    smtp.starttls()
    smtp.login(username, password)
    smtp.sendmail(sender, recipient, 
        "From: %s\nTo: %s\nSubject: %s\n%s" % (sender, recipient, subject, message))
    smtp.quit()

    print("Sent message.")
except Exception as exception:
    print(exception)

Output:

Sent message.