Dmitry Goldenberg added the comment:
Yes, it's a question which could lend itself well to a documentation issue.
I've looked at things like:
https://stackoverflow.com/questions/54047021/python-smtplib-how-to-use-disposition-notification-to
https://stackoverflow.com/questions/40369
New submission from Dmitry Goldenberg :
Is there a reliable way to certify (ensure, track) the delivery of an email
message when using smtplib?
For example:
Disposition-Notification-To message header which enables the e-mail reader of
the recipient to send confirmation e-mail when the
