assertion  retraction  graph  subject          predicate        object           datatype  annotation
1          0           graph  obo:CHEBI_25806  rdfs:subClassOf  obo:CHEBI_33304  _IRI      
1          0           graph  obo:CHEBI_26835  rdfs:subClassOf  obo:CHEBI_33304  _IRI      
1          0           graph  obo:CHEBI_36962  rdfs:subClassOf  obo:CHEBI_33304  _IRI