rdf.py

#!/usr/bin/env python3
"""Print publication PMID values grouped by RDF subject URI."""

try:
    from rdflib import Graph, URIRef
except ImportError as exc:
    raise SystemExit("Missing dependency: install rdflib with `python3 -m pip install rdflib`.") from exc


RDF_URL = "https://edrn.jpl.nasa.gov/cancerdataexpo/rdf-data/publications/@@rdf"
PMID = URIRef("http://edrn.nci.nih.gov/rdf/schema.rdf#pmid")


def main() -> None:
    graph = Graph()
    graph.parse(RDF_URL)

    for subject in sorted(set(graph.subjects(predicate=PMID)), key=str):
        pmids = sorted({str(pmid) for pmid in graph.objects(subject, PMID)})
        for pmid in pmids:
            print(f"{subject}\t{pmid}")


if __name__ == "__main__":
    main()