code: def _debug_check(self):
          
          # old_start = 0
          old_end = 0
          old_sort = ""
          for segment in self._list:
              if segment.start <= old_end and segment.sort == old_sort:
                  raise AngrCFGError("Error in SegmentList: blocks are not merged")
              # old_start = start
              old_end = segment.end
              old_sort = segment.sort
docs: Iterates over list checking segments with same sort do not overlap
  
          :raise: Exception: if segments overlap space with same sort