code: def _psplit(self):
          
  
          nsplit_list = self._nsplit()
          psplit_list = [ ]
  
          for si in nsplit_list:
              psplit_list.extend(si._ssplit())
  
          return psplit_list
docs: Split `self` at both north and south poles.
  
          :return: A list of split StridedIntervals