docs: def _cursor_up(self, value):
          """
          Moves the cursor up by ``value``.
          """
          value = int(value)
          if value == 0:
              value = 1
          self._cursor.clearSelection()
          self._cursor.movePosition(self._cursor.Up, self._cursor.MoveAnchor, value)
          self._last_cursor_pos = self._cursor.position()