assertion  retraction  graph  subject          predicate        object           datatype  annotation
1          0           graph  obo:CHEBI_33424  rdfs:subClassOf  obo:CHEBI_26835  _IRI      
1          0           graph  obo:CHEBI_26822  rdfs:subClassOf  obo:CHEBI_26835  _IRI      
1          0           graph  obo:CHEBI_33261  rdfs:subClassOf  obo:CHEBI_26835  _IRI