Вот рабочий пример для отправки текстовых и HTML-писем из Python с использованием smtplib вместе с параметрами CC и BCC.

https://varunver.wordpress.com/2017/ 01/26 / python-smtplib-send-plaintext-and-html-emails /

#!/usr/bin/env python
import smtplib
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText

def send_mail(params, type_):
      email_subject = params['email_subject']
      email_from = "from_email@domain.com"
      email_to = params['email_to']
      email_cc = params.get('email_cc')
      email_bcc = params.get('email_bcc')
      email_body = params['email_body']

      msg = MIMEMultipart('alternative')
      msg['To'] = email_to
      msg['CC'] = email_cc
      msg['Subject'] = email_subject
      mt_html = MIMEText(email_body, type_)
      msg.attach(mt_html)

      server = smtplib.SMTP('YOUR_MAIL_SERVER.DOMAIN.COM')
      server.set_debuglevel(1)
      toaddrs = [email_to] + [email_cc] + [email_bcc]
      server.sendmail(email_from, toaddrs, msg.as_string())
      server.quit()

# Calling the mailer functions
params = {
    'email_to': 'to_email@domain.com',
    'email_cc': 'cc_email@domain.com',
    'email_bcc': 'bcc_email@domain.com',
    'email_subject': 'Test message from python library',
    'email_body': '
Hello World
'
}
for t in ['plain', 'html']:
    send_mail(params, t)