import smtplib

s = smtplib.SMTP("smtp.gmail.com")
s.ehlo()
s.starttls()
s.ehlo()
s.login("username", "password")
msg = "From: username@gmail.com\r\nTo: other.user@gmail.com\r\nSubject: Testing 1 2 3\r\n\r\n"
msg += "This is a test, only a test."
s.sendmail("username@gmail.com", "other.user@gmail.com", msg)
s.quit()