assertion  retraction  graph  subject         predicate        object           datatype    annotation
1          0           graph  obo:CHEBI_8232  rdfs:label       piperacillin     xsd:string  
1          0           graph  obo:CHEBI_8232  oio:id           CHEBI:8232       xsd:string  
1          0           graph  obo:CHEBI_8232  rdfs:subClassOf  obo:CHEBI_88187  _IRI        
1          0           graph  obo:CHEBI_8232  rdf:type         owl:Class        _IRI