Has event leaf node

@prefix omop: <https://w3id.org/omop/ontology/> .
@prefix owl: <http://www.w3.org/2002/07/owl#> .
@prefix owlready: <http://www.lesfleursdunormal.fr/static/_downloads/owlready_ontology.owl#> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

omop:has_event a owl:FunctionalProperty,
        owl:ObjectProperty ;
    rdfs:label "Has event"^^xsd:string ;
    owlready:python_name "event"^^xsd:string ;
    rdfs:comment """For Cost: If the Cost record is related to another record in the database, this field is the primary key of the linked record.
Put the primary key of the linked record, if applicable, here."""@en,
        """For Observation: If the Observation record is related to another record in the database, this field is the primary key of the linked record.
Put the primary key of the linked record, if applicable, here. See the [ETL Conventions for the OBSERVATION](https://ohdsi.github.io/CommonDataModel/cdm60.html#observation) table for more details."""@en ;
    rdfs:domain [ a owl:Class ;
            owl:unionOf ( omop:Cost omop:Observation omop:Note ) ] ;
    omop:omop_cdm_name "cost.cost_event_id#309 AS Thing"^^xsd:string,
        "note.note_event_id#179 AS Thing"^^xsd:string,
        "observation.observation_event_id#167 AS Thing"^^xsd:string .