Traceback (most recent call last):
  File "/usr/lib/ubuntu-sso-client/ubuntu-sso-login", line 63, in <module>
    from ubuntu_sso.main import main
  File "/usr/lib/python2.7/dist-packages/ubuntu-sso-client/ubuntu_sso/main/__init__.py", line 67, in <module>
    from ubuntu_sso.main import linux
  File "/usr/lib/python2.7/dist-packages/ubuntu-sso-client/ubuntu_sso/main/linux.py", line 458, in <module>
    from ubuntu_sso.main import glib
  File "/usr/lib/python2.7/dist-packages/ubuntu-sso-client/ubuntu_sso/main/glib.py", line 37, in <module>
    from gi.repository import GLib, Gdk, Gtk
  File "/usr/lib/python2.7/dist-packages/gi/importer.py", line 76, in load_module
    dynamic_module._load()
  File "/usr/lib/python2.7/dist-packages/gi/module.py", line 224, in _load
    overrides_modules = __import__('gi.overrides', fromlist=[self._namespace])
  File "/usr/lib/python2.7/dist-packages/gi/overrides/Gdk.py", line 349, in <module>
    raise RuntimeError("Gdk couldn't be initialized")
RuntimeError: Gdk couldn't be initialized