code: def _addSexSpecificity(self, subject_id, sex):
          
          self.graph.addTriple(subject_id, self.globaltt['has_sex_specificty'], sex)
docs: Add sex specificity to a subject (eg association node)
  
          In our modeling we use this to add a qualifier to a triple
          for example, this genotype to phenotype association
          is specific to this sex (see MGI, IMPC)
  
          This expects the client to define the ontology term
          for sex (eg PATO)
  
          Note this class is probably not the right place for this
          method, but putting here until a better home is found
          :param subject_id:
          :param sex:
          :return: