system-config-samba crashes as can't find /etc/libuser.conf

john@NewDesktop:~$ sudo system-config-samba
[sudo] password for john:

(system-config-samba:23200): IBUS-WARNING **: The owner of /home/john/.config/ibus/bus is not root!
Traceback (most recent call last):
  File "/usr/sbin/system-config-samba", line 45, in <module>
    mainWindow.MainWindow(debug_flag)
  File "/usr/share/system-config-samba/mainWindow.py", line 121, in __init__
    self.basic_preferences_win = basicPreferencesWin.BasicPreferencesWin(self, self.xml, self.samba_data, self.samba_backend, self.main_window)
  File "/usr/share/system-config-samba/basicPreferencesWin.py", line 97, in __init__
    self.admin = libuser.admin()
SystemError: could not open configuration file `/etc/libuser.conf': No such file or directory

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: system-config-samba 1.2.63-0ubuntu6
ProcVersionSignature: Ubuntu 4.4.0-62.83-generic 4.4.40
Uname: Linux 4.4.0-62-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.5
Architecture: amd64
CurrentDesktop: Unity
Date: Mon Feb 13 15:18:42 2017
InstallationDate: Installed on 2016-12-08 (67 days ago)
InstallationMedia: Ubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
PackageArchitecture: all
SourcePackage: system-config-samba
UpgradeStatus: No upgrade log present (probably fresh install)