How to restrict sending emails via smtp in Python?

Question

Python

def send_email(from_addr, to_addr, body_text):

    msg_body = ""
    parts = ["From: %s" % from_addr,
            "To: %s" % to_addr,
            "MIME-Version: 1.0",
            "Content-type: text/html",
            "Subject: %s" % subject,
            "",
            body_text
            , "\r\n"]
    msg_body = "\r\n".join(parts)
    server = SMTP(host, 465)
    # server.set_debuglevel(1)
    server.ehlo()
    server.login(usrnme,pswd)
    server.sendmail(from_addr, to_addr, msg_body)
    server.quit()

And sending

send_email("@gmail.com", "@gmail.com", " %s" %(data))

I launch the program, and I receive letters endlessly.
Is it possible to somehow limit it to one letter?