Some entities/classes present in knowledge-graphs have operations performed on them like 'Union', 'Intersection' etc. Below is one ontology file which has has lots of union operations on various of its classes.

ontology -> Link

Problem : I wanted to extract all the classes involved with the same union operation. If for example Classes A,B and C are associated with an union operation. I would want them together.

Tried so far : I have tried using rdflib and went through all the triples. But none of the triples contain the union info, even though there are union operation in the file.

I have also tried with owlready2, it has a method to list all the disjoint classes, but no functionality to get to union of classes.

It would be great help if there is a way to get the classes involved in a particular union operation.

PS : I am using python for my project