GPG Error handling

quite often I do observe this exception with an abort of my backup.

   do_backup(action)
 File "/usr/local/bin/duplicity", line 1515, in do_backup
   check_last_manifest(col_stats) # not needed for full backup
 File "/usr/local/bin/duplicity", line 1217, in check_last_manifest
   last_backup_set.check_manifests()
 File "/usr/local/Cellar/duplicity/0.7.14_1/libexec/lib/python2.7/site-packages/duplicity/collections.py", line 208, in check_manifests
   remote_manifest = self.get_remote_manifest()
 File "/usr/local/Cellar/duplicity/0.7.14_1/libexec/lib/python2.7/site-packages/duplicity/collections.py", line 244, in get_remote_manifest
   (self.remote_manifest_name, str(message)))
UnicodeEncodeError: 'ascii' codec can't encode characters in position 67-68: ordinal not in range(128)

I recommend to use in collections.py, line 244

                    (self.remote_manifest_name, message.encode('ascii', 'ignore')))

rather than str(message)

after changing it this way, my backups are working again