Getting "empty" attachment with smtplib

[Dieter Maurer]

Tobiah <toby at tobiah.org> writes:

> I just found out that the attachment works fine
> when I read the mail from the gmail website.  Thunderbird
> complains that the attachment is empty.

The MIME standard (a set of RFCs) specifies how valid messages
with attachments should look like.

Fetch the mail (unprocessed if possible) and look at its
structure. If it is conformant to the MIME standard, then
"Thunderbird" made a mistake; otherwise, something went wrong
with the message construction.

I can already say that "smtplib" is not to blame. It is (mostly) unconcerned
with the internal structure of the message -- and by itself
will not empty attachments.