I found that if I move a bit the "import requests_unixsocket" line (in file LivepatchService.py), then the software-properties-gtk call *works*. Please somebody either propagate this solution (if it is a true solution), or tell me how to propagate. (I do not know shat is exactly happening. Whether the try-clause partly succeeds, then rolls back?..)
$ sudo -s # cd /usr/lib/python3/dist-packages/softwareproperties # diff -u4 LivepatchService.py.ORI LivepatchService.py.MY --- LivepatchService.py.ORI 2019-06-24 14:46:07.000000000 +0200 +++ LivepatchService.py.MY 2019-06-24 14:54:31.000000000 +0200 @@ -23,13 +23,12 @@ import logging import gi from gi.repository import Gio, GLib, GObject +import requests_unixsocket try: import dateutil.parser - import requests_unixsocket - gi.require_version('Snapd', '1') from gi.repository import Snapd except(ImportError, ValueError): pass # cp LivepatchService.py.MY LivepatchService.py $ software-properties-gtk {OK, works! The dialog is popping up.} -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to software-properties in Ubuntu. https://bugs.launchpad.net/bugs/1830914 Title: software-properties-gtk does not run at all! Status in software-properties package in Ubuntu: New Bug description: software-properties-gtk does not even start! $ software-properties-gtk --debug ENABLED COMPS: {'universe', 'main'} INTERNET COMPS: {'universe', 'main'} MAIN SOURCES URI: http://archive.ubuntu.com/ubuntu Comps: ['main'] Enabled: True Valid: True MatchURI: archive.ubuntu.com/ubuntu BaseURI: http://archive.ubuntu.com/ubuntu URI: http://archive.ubuntu.com/ubuntu Comps: ['universe'] Enabled: True Valid: True MatchURI: archive.ubuntu.com/ubuntu BaseURI: http://archive.ubuntu.com/ubuntu CHILD SOURCES URI: http://archive.ubuntu.com/ubuntu Comps: ['main'] Enabled: True Valid: True MatchURI: archive.ubuntu.com/ubuntu BaseURI: None URI: http://archive.ubuntu.com/ubuntu Comps: ['universe'] Enabled: True Valid: True MatchURI: archive.ubuntu.com/ubuntu BaseURI: None URI: http://archive.ubuntu.com/ubuntu Comps: ['main'] Enabled: True Valid: True MatchURI: archive.ubuntu.com/ubuntu|security.ubuntu.com BaseURI: http://security.ubuntu.com/ubuntu/ URI: http://archive.ubuntu.com/ubuntu Comps: ['universe'] Enabled: True Valid: True MatchURI: archive.ubuntu.com/ubuntu|security.ubuntu.com BaseURI: http://security.ubuntu.com/ubuntu/ URI: http://archive.ubuntu.com/ubuntu Comps: ['universe', 'main'] Enabled: True Valid: True MatchURI: archive.ubuntu.com/ubuntu BaseURI: None CDROM SOURCES SOURCE CODE SOURCES DISABLED SOURCES ISV Traceback (most recent call last): File "/usr/bin/software-properties-gtk", line 100, in <module> app = SoftwarePropertiesGtk(datadir=options.data_dir, options=options, file=file) File "/usr/lib/python3/dist-packages/softwareproperties/gtk/SoftwarePropertiesGtk.py", line 200, in __init__ self.init_livepatch() File "/usr/lib/python3/dist-packages/softwareproperties/gtk/SoftwarePropertiesGtk.py", line 1482, in init_livepatch self.livepatch_page = LivepatchPage(self) File "/usr/lib/python3/dist-packages/softwareproperties/gtk/LivepatchPage.py", line 51, in __init__ self._lps = LivepatchService() File "/usr/lib/python3/dist-packages/softwareproperties/LivepatchService.py", line 93, in __init__ self._session = requests_unixsocket.Session() NameError: name 'requests_unixsocket' is not defined {Exited with code 1.} $ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 19.04 Release: 19.04 Codename: disco $ dpkg-query -l software-properties-gtk python3-requests-unixsocket Desired=Unknown/Install/Remove/Purge/Hold | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend |/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad) ||/ Name Version Architecture Description +++-===========================-============-============-=============================================================== ii python3-requests-unixsocket 0.1.5-3 all Use requests to talk HTTP via a UNIX domain socket - Python 3.x ii software-properties-gtk 0.97.11 all manage the repositories that you install software from (gtk) $ sudo apt-get update {Works.} $ sudo apt-get dist-upgrade {Works.} To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/software-properties/+bug/1830914/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp