docs: def insert(self, index, item):
          """See list.insert."""
          super(ObservableList, self).insert(index, item)
          length = len(self)
          if index >= length:
              index = length - 1
          elif index < 0:
              index += length - 1
              if index < 0:
                  index = 0
          self._notify_add_at(index)