[Checkins] [zopefoundation/zope.sendmail] 21bbf6: make `flake8` happy

[Dieter Maurer]

  Branch: refs/heads/using-bytes-for-messages
  Home:   https://github.com/zopefoundation/zope.sendmail
  Commit: 21bbf65cfa960da3774b16cde067c78c25c37e1c
      https://github.com/zopefoundation/zope.sendmail/commit/21bbf65cfa960da3774b16cde067c78c25c37e1c
  Author: dieter <dieter at handshake.de>
  Date:   2020-07-21 (Tue, 21 Jul 2020)

  Changed paths:
    M src/zope/sendmail/delivery.py

  Log Message:
  -----------
  make `flake8` happy