Traceback (most recent call last):
  File "/usr/bin/update-manager", line 38, in <module>
    from UpdateManager.UpdateManager import UpdateManager
  File "/usr/lib/python3/dist-packages/UpdateManager/UpdateManager.py", line 49, in <module>
    from .UnitySupport import UnitySupport
  File "/usr/lib/python3/dist-packages/UpdateManager/UnitySupport.py", line 31, in <module>
    gi.require_version('Unity', '7.0')
  File "/usr/lib/python3/dist-packages/gi/__init__.py", line 118, in require_version
    raise ValueError('Namespace %s not available' % namespace)
ValueError: Namespace Unity not available