code: def build_transitive_closures(self):
          
          self.component_counter = 0
          for rel, tc_dict in ((self.isa_objects, self.isa_closure),
                               (self.partof_objects, self.partof_closure),
                               (self.isa_or_partof_objects,
                                   self.isa_or_partof_closure)):
              self.build_transitive_closure(rel, tc_dict)
docs: Build the transitive closures of the hierarchy.
  
          This method constructs dictionaries which contain terms in the
          hierarchy as keys and either all the "isa+" or "partof+" related terms
          as values.