IndexError: list index out of range

[Neberheim]

I am attempting to export OmniFocus 3 projects using the built-in taskpaper support, and then import into Things 3.

• Here is what is returned:

Traceback (most recent call last):
  File "/usr/local/bin/popthings", line 8, in <module>
    sys.exit(cli())
  File "/usr/local/bin/popthings.py", line 895, in cli
    taskpaper_to_things(template)
  File "/usr/local/bin/popthings.py", line 886, in taskpaper_to_things
    things_json = taskpaper_template_to_things_json(text)
  File "/usr/local/bin/popthings.py", line 797, in taskpaper_template_to_things_json
    things_objs = things_objects_from_taskpaper_tree(tree)
  File "/usr/local/bin/popthings.py", line 720, in things_objects_from_taskpaper_tree
    things_nodes[-1].add_item(things_obj)
IndexError: list index out of range

Here is the file as created by OmniFocus: OmniFocus.txt

Any idea if the issue is with how OmniFocus parses to taskpaper, or with popthings?

MacOS 10.15.7
OmniFocus 3.11.2
Things 3.13.8
pip 21.0.1