Comment 2 for bug 1736164

Description of problem:
With the update from Fedora 25 to Fedora 26 Workstation, backups with deja-dup/duplicity are failing

Version-Release number of selected component (if applicable):
duplicity 0.7.13.1
deja-dup 34.3

How reproducible:
Always (scheduled and manually started backup)

Steps to Reproduce:
1. Wait for the scheduled backup to start or start it via the "Backup now" button
2. Some or a large number of files might get backed up, then the backup stops with "Failed with an unknown error"
3.

Actual results:
Backup fails

Expected results:
Backup completes as it always did

Additional info:
Traceback (most recent call last):
  File "/usr/bin/duplicity", line 1540, in <module>
    with_tempdir(main)
  File "/usr/bin/duplicity", line 1534, in with_tempdir
    fn()
  File "/usr/bin/duplicity", line 1385, in main
    do_backup(action)
  File "/usr/bin/duplicity", line 1516, in do_backup
    incremental_backup(sig_chain)
  File "/usr/bin/duplicity", line 668, in incremental_backup
    globals.backend)
  File "/usr/bin/duplicity", line 453, in write_multivol
    (tdp, dest_filename, vol_num)))
  File "/usr/lib64/python2.7/site-packages/duplicity/asyncscheduler.py", line 146, in schedule_task
    return self.__run_synchronously(fn, params)
  File "/usr/lib64/python2.7/site-packages/duplicity/asyncscheduler.py", line 172, in __run_synchronously
    ret = fn(*params)
  File "/usr/bin/duplicity", line 452, in <lambda>
    vol_num: put(tdp, dest_filename, vol_num),
  File "/usr/bin/duplicity", line 341, in put
    backend.put(tdp, dest_filename)
  File "/usr/lib64/python2.7/site-packages/duplicity/backend.py", line 376, in inner_retry
    % exception_traceback())
  File "/usr/lib64/python2.7/site-packages/duplicity/util.py", line 51, in exception_traceback
    return uexc(msg)
  File "/usr/lib64/python2.7/site-packages/duplicity/util.py", line 79, in uexc
    e = unicode(e).encode('utf-8')
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 746: ordinal not in range(128)