code: def _uniq_pixels_iterator(self):
          
          intervals_uniq_l = IntervalSet.to_nuniq_interval_set(self._interval_set)._intervals
          for uniq_iv in intervals_uniq_l:
              for uniq in range(uniq_iv[0], uniq_iv[1]):
                  yield uniq
docs: Generator giving the NUNIQ HEALPix pixels of the MOC.
  
          Returns
          -------
          uniq :
              the NUNIQ HEALPix pixels iterator