assertion  retraction  graph  subject          predicate        object           datatype  annotation
1          0           graph  obo:CHEBI_27171  rdfs:subClassOf  obo:CHEBI_38166  _IRI      
1          0           graph  obo:CHEBI_26979  rdfs:subClassOf  obo:CHEBI_38166  _IRI      
1          0           graph  obo:CHEBI_35259  rdfs:subClassOf  obo:CHEBI_38166  _IRI