Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/defer/__init__.py", line 472, in _inline_callbacks
    result = gen.throw(result.type, result.value, result.traceback)
  File "/usr/lib/python2.7/dist-packages/aptdaemon/gtkwidgets.py", line 633, in _run
    yield self._transaction.run()
AuthorizationFailed: org.freedesktop.PolicyKit.Error.Failed: ('system-bus-name', {'name':  ':1.38'}): org.debian.apt.update-cache