Adds a resource property as an URI string.
Previous values for the same property are kept.
This method applies to properties with a [rdfs:range](rdf-ontology.html#rdfs:range) that points to a non-literal class (i.e. a subclass of [rdfs:Resource](rdf-ontology.html#rdfs:Resource)).
This method is meant for RDF properties allowing multiple values, see [nrl:maxCardinality](nrl-ontology.html#nrl:maxCardinality).
This function produces similar RDF to [method@Resource.add_relation], although it requires that the URI is previously known.
| this |
the `TrackerResource` |
| property_uri |
a string identifying the property to modify |
| value |
the property object |