code: def set(self, id_, lineno, value='', fname=None, args=None):
          
          if fname is None:
              if CURRENT_FILE:
                  fname = CURRENT_FILE[-1]
              else:  # If no files opened yet, use owns program fname
                  fname = sys.argv[0]
          self.table[id_] = ID(id_, args, value, lineno, fname)
docs: Like the above, but issues no warning on duplicate macro
              definitions.