code: def cpe_subset(cls, source, target):
          
  
          # If any pairwise comparison returned something other than SUBSET
          # or EQUAL, then SUBSET is False.
          for att, result in CPESet2_3.compare_wfns(source, target):
              isSubset = result == CPESet2_3.LOGICAL_VALUE_SUBSET
              isEqual = result == CPESet2_3.LOGICAL_VALUE_EQUAL
              if (not isSubset) and (not isEqual):
                  return False
          return True
docs: Compares two WFNs and returns True if the set-theoretic relation
          between the names is (non-proper) SUBSET.
  
          :param CPE2_3_WFN source: first WFN CPE Name
          :param CPE2_3_WFN target: seconds WFN CPE Name
          :returns: True if the set relation between source and target
              is SUBSET, otherwise False.
          :rtype: boolean