Traceback (most recent call last):
  File "/usr/lib/ubiquity/plugins/ubi-partman.py", line 1103, in on_partition_list_edit_activate
    self.partman_edit_dialog(devpart, partition)
  File "/usr/lib/ubiquity/ubiquity/plugin.py", line 44, in wrapper
    return target(self, *args, **kwargs)
  File "/usr/lib/ubiquity/plugins/ubi-partman.py", line 879, in partman_edit_dialog
    for script, arg, option in partition['method_choices']:
KeyError: 'method_choices'