Failed to install: deb822.py, line 38: ImportError: No module named 'chardet'

Error on update, no real impact on the regular use of Ubuntu

ProblemType: Package
DistroRelease: Ubuntu 16.04
Package: ttf-mscorefonts-installer 3.4+nmu1ubuntu2
ProcVersionSignature: Ubuntu 4.15.0-43.46~16.04.1-generic 4.15.18
Uname: Linux 4.15.0-43-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia_drm nvidia_modeset nvidia
ApportVersion: 2.20.1-0ubuntu2.18
Architecture: amd64
Date: Thu Jan 3 06:40:02 2019
DpkgHistoryLog:
 Start-Date: 2019-01-03 06:39:53
 Commandline: /usr/bin/unattended-upgrade
 Upgrade: tzdata:amd64 (2018g-0ubuntu0.16.04, 2018i-0ubuntu0.16.04)
ErrorMessage: problèmes de dépendances - laissé non configuré
InstallationDate: Installed on 2018-05-31 (218 days ago)
InstallationMedia: Ubuntu 16.04.4 LTS "Xenial Xerus" - Release amd64 (20180228)
PackageArchitecture: all
RelatedPackageVersions:
 dpkg 1.18.4ubuntu1.5
 apt 1.2.29
SourcePackage: msttcorefonts
Title: package ttf-mscorefonts-installer 3.4+nmu1ubuntu2 failed to install/upgrade: problèmes de dépendances - laissé non configuré
UpgradeStatus: No upgrade log present (probably fresh install)

Update-notifier-common configuration (3.168.9) ...
Traceback (most recent call last):
  File "/ usr / lib / update-notifier / package-data-downloader", line 24, in <module>
    import debian.deb822
  File "/usr/lib/python3/dist-packages/debian/deb822.py", line 38, in <module>
    import chardet
ImportError: No module named 'chardet'
dpkg: error processing update-notifier-common package (--configure):
 the installed post-installation script subprocess returned a status exit error 1