sending email in python with gmail

A Python nugget from Programming Your Home (review) I wanted to share from p97:

import smtplib
def send_email(subject, message)
    recipient = 'your_email_recipient@domain.tld'
    gmail_sender = 'your_gmail_account@gmail.com'
    gmail_password = 'your_gmail_password'

    #use tls
    gmail_smtp = smtplib.SMTP('smtp.gmail.com', 587)
    gmail_smtp.ehlo()
    gmail_smtp.starttls()
    gmail_smtp.ehlo()

    #login
    gmail_smtp.login(gmail_send, gmail_password)

    #message formatting
    mail_header = 'To: ' + recipient + '\n' + 'From: ' + gmail_sender + '\n' + 'Subject: ' + subject + '\n'
    message_body = message
    mail message = mail_header + '\n ' + message_body + '\n\n'

    #send
    gmail_smtp.sendmail(gmail_sender, recipient, mail_message)

    #close
    gmail_smtp.close()