Comment 10 for bug 633101

Duplicity fails since a few weeks, have updated my desktop to Ubuntu 15.04 and cleaned up everything, de-installed Duplicity and re-installed it, cleaned the harddrive from all old duplicity files but still won't work.

Traceback (most recent call last):
  File "/usr/bin/duplicity", line 1500, in <module>
    with_tempdir(main)
  File "/usr/bin/duplicity", line 1494, in with_tempdir
    fn()
  File "/usr/bin/duplicity", line 1343, in main
    do_backup(action)
  File "/usr/bin/duplicity", line 1376, in do_backup
    globals.archive_dir).set_values()
  File "/usr/lib/python2.7/dist-packages/duplicity/collections.py", line 698, in set_values
    self.get_backup_chains(partials + backend_filename_list)
  File "/usr/lib/python2.7/dist-packages/duplicity/collections.py", line 821, in get_backup_chains
    add_to_sets(f)
  File "/usr/lib/python2.7/dist-packages/duplicity/collections.py", line 810, in add_to_sets
    if set.add_filename(filename):
  File "/usr/lib/python2.7/dist-packages/duplicity/collections.py", line 102, in add_filename
    (self.volume_name_dict, filename)
AssertionError: ({2: 'duplicity-inc.20161110T115644Z.to.20161120T105000Z.vol2.difftar.gpg', 3: 'duplicity-inc.20161110T115644Z.to.20161120T105000Z.vol3.difftar.gpg'}, 'duplicity-inc.20161110T115644Z.to.20161120T105000Z.vol3.difftar.gpg')

No clue what this means, do I need a different backup program now?.