code: def set_pair(self, term1, term2, value, **kwargs):
  
          
  
          key = self.key(term1, term2)
          self.keys.update([term1, term2])
          self.pairs[key] = value
docs: Set the value for a pair of terms.
  
          Args:
              term1 (str)
              term2 (str)
              value (mixed)