code: def pseudoify(self):
          assert self.is_toplevel
          assert self.is_multi
          assert len(self.multi_rep.siblings) > 0
          rep = self.multi_rep
          start = min([s.start for s in rep.siblings + [rep]])
          end = max([s.end for s in rep.siblings + [rep]])
          parent = Feature(None)
          parent._pseudo = True
          parent._seqid = self._seqid
          parent.set_coord(start, end)
          parent._strand = self._strand
          for sibling in rep.siblings + [rep]:
              parent.add_child(sibling, rangecheck=True)
          parent.children = sorted(parent.children)
          rep.siblings = sorted(rep.siblings)
          return parent