def test_iadd(self, evt):
        rval = event.ReturnValue(append_events=[evt])
        rval2 = event.ReturnValue(eat=True, append_events=[evt])
        rset = event.ResultSet()

        rset += rval
        rset += rval2
        rset += None
        assert rset.eat
        assert rset.append_events == [evt, evt]
def _rename_item_names(self, start_index):
    for index, item in enumerate(self._items[start_index:]):
      item.label.set_label(self._get_item_name(index + 1 + start_index))