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 f(i):
        start = W[i]
        extent = W[i + 1] - W[i]
        rv = te.reduce_axis((0, extent))
        return te.sum(X[rv + start], axis=rv)