При обновлении apt-listchanges вылетает при отправке электронной почты

Get:1 http://archive.ubuntu.com/ubuntu bionic-updates/main i386 libsqlite3-0 i386 3.22.0-1ubuntu0.1 [533 kB]
Get:2 http://archive.ubuntu.com/ubuntu bionic-updates/main i386 firefox i386 67.0.3+build1-0ubuntu0.18.04.1 [50.6 MB]
Get:3 http://archive.ubuntu.com/ubuntu bionic-updates/main i386 firefox-locale-de i386 67.0.3+build1-0ubuntu0.18.04.1 [447 kB]     
Fetched 51.6 MB in 18s (2859 kB/s)                                                                                                 
apt-listchanges: Changelogs werden gelesen...
Traceback (most recent call last):
  File "/usr/bin/apt-listchanges", line 281, in <module>
    main(config)
  File "/usr/bin/apt-listchanges", line 145, in main
    _send_email(changes, lambda: _("apt-listchanges: changelogs for %s") % hostname)
  File "/usr/bin/apt-listchanges", line 267, in _send_email
    apt_listchanges.mail_changes(config, changes, subject_getter())
  File "/usr/share/apt-listchanges/apt_listchanges.py", line 65, in mail_changes
    'subject': subject})
  File "/usr/share/apt-listchanges/ALCLog.py", line 36, in info
    print(_("apt-listchanges: %(msg)s") % {'msg': msg}, file=sys.stdout);

config для apt-listchanges cat

/etc/apt/listchanges.conf
[apt]
frontend=mail
email_address=root
confirm=0
save_seen=/var/lib/apt/listchanges.db
which=both

Версия

apt-cache policy apt-listchanges 
apt-listchanges:
  Installiert:           3.16
  Installationskandidat: 3.16

      Versionstabelle:
     *** 3.16 500
        500 http://archive.ubuntu.com/ubuntu bionic/main i386 Packages
        100 /var/lib/dpkg/status

и

 python --version
Python 3.6.8

В моей системе несколько пакетов из предложенных .

    apt-show-versions | grep proposed
libegl-mesa0:i386/bionic-proposed 19.0.2-1ubuntu1.1~18.04.1 uptodate
libgbm1:i386/bionic-proposed 19.0.2-1ubuntu1.1~18.04.1 uptodate
libnm-glib4:i386/bionic-proposed 1.10.14-0ubuntu2 uptodate
libnm-util2:i386/bionic-proposed 1.10.14-0ubuntu2 uptodate
libnm0:i386/bionic-proposed 1.10.14-0ubuntu2 uptodate
linux-headers-4.15.0-52:all/bionic-proposed 4.15.0-52.56 uptodate
linux-headers-4.15.0-52-generic:i386/bionic-proposed 4.15.0-52.56 uptodate
linux-image-4.15.0-52-generic:i386/bionic-proposed 4.15.0-52.56 uptodate
linux-modules-4.15.0-52-generic:i386/bionic-proposed 4.15.0-52.56 uptodate
linux-modules-extra-4.15.0-52-generic:i386/bionic-proposed 4.15.0-52.56 uptodate
linux-tools-4.15.0-52:i386/bionic-proposed 4.15.0-52.56 uptodate
linux-tools-4.15.0-52-generic:i386/bionic-proposed 4.15.0-52.56 uptodate
network-manager:i386/bionic-proposed 1.10.14-0ubuntu2 uptodate
openvpn:i386/bionic-proposed 2.4.4-2ubuntu1.3 uptodate

но я не думаю, что это вызывает ошибку. apt-config dump

Обычно я получаю электронные письма через exim4 на localhost.