Comment 5 for bug 426282

This second patch skips the par2 files when building up the sets and chains of backups, used for the collection-status command. Without it, the par2 files were considered as being incomplete backups:

Also found 0 backup sets not part of any chain,
and 2 incomplete backup sets.
These may be deleted by running duplicity with the --cleanup option.

This is misleading because the cleanup command won't remove those files (of course!) and we'll still get the "incomplete backup sets" message on the next collection-status command.
After this patch is applied, a duplicity collection-status on the same backup profile says:

No orphaned or incomplete backup sets found.

Hopefully there's no side effect. Haven't noticed any for now, but it may require more testing.