`ont['event-of-causation'].word_closure()` is empty with any depth

[sidsvash26]

ont['event-of-causation'].word_closure() returns an empty set with any chosen depth. To replicate the issue, you can run this:

from pytrips.ontology import load
ont = load()
for i in range(10):
    ont.max_wn_depth = i
    print("Number of words in closure with depth {} -  {}".format(i, len(ont['event-of-causation'].word_closure())))

Output:

Number of words in closure with depth 0 -  0
Number of words in closure with depth 1 -  0
Number of words in closure with depth 2 -  0
Number of words in closure with depth 3 -  0
Number of words in closure with depth 4 -  0
Number of words in closure with depth 5 -  0
Number of words in closure with depth 6 -  0
Number of words in closure with depth 7 -  0
Number of words in closure with depth 8 -  0
Number of words in closure with depth 9 -  0

Is this something expected or a bug?

[sidsvash26]

Just looked at the ontology.py code and realized this will be true for all ontology types whose wordnet_sense_keys is empty in the ontology.json file.

[mrmechko]

Many ontology types don't actually contain any word/wordnet entries.