Traceback (most recent call last):
  File "/usr/bin/software-properties-gtk", line 37, in <module>
    from softwareproperties.gtk.SoftwarePropertiesGtk import SoftwarePropertiesGtk
  File "/usr/lib/python3/dist-packages/softwareproperties/gtk/SoftwarePropertiesGtk.py", line 34, in <module>
    from aptdaemon import client
  File "/usr/lib/python3/dist-packages/aptdaemon/client.py", line 43, in <module>
    import gobject as GObject
ImportError: No module named gobject