def METHOD_NAME(endpoint):
    """
        Retrieve UPRNs as instantiated way back from static OS download 
        using FME workflow
        Returns dict of {'bldgIRI': set of UPRNs}
    """
    sparql = SPARQLWrapper(endpoint)
    sparql.setReturnFormat(JSON)
    query_string = f"""
    PREFIX ocgml: <http://www.theworldavatar.com/ontology/ontocitygml/citieskg/OntoCityGML.owl#>
    PREFIX xsd: <http://www.w3.org/2001/XMLSchema#> 
    PREFIX osid: <http://www.theworldavatar.com/ontology/ontocitygml/citieskg/OntoOSID.owl#>
    SELECT DISTINCT ?bldg ?cityobj ?uprns
    WHERE {{ 
    GRAPH <{namespace}building/>                             
            {{ ?bldg ocgml:objectClassId 26 .
            BIND(IRI(REPLACE(str(?bldg), "building", "cityobject")) AS ?cityobj) 
            }}
            {{ # UPRNs from FME workflow
            SELECT DISTINCT ?cityobj ?uprns
            WHERE {{
                GRAPH <{namespace}cityobjectgenericattrib/>
                    {{ OPTIONAL {{
                        ?attr ocgml:attrName "OS_UPRNs" ;
                            ocgml:cityObjectId ?cityobj ;
                            ocgml:strVal ?uprns .
                        }}
                    }}
                }}
            }}
    }}
    """
    sparql.setQuery(query_string)
    results = sparql.query().convert()
    # Create dict of building IRIs and set of UPRNs
    res = {r['bldg']['value']: set() if not r.get('uprns') else 
                               set(r['uprns']['value'].split(','))
                               for r in results['results']['bindings']}
    return res