def test_get_min_by_period_Y(self): x = TimeSeries([ (datetime.date(2001, 1, 31), 1), (datetime.date(2001, 2, 28), 2), (datetime.date(2001, 3, 31), 3), (datetime.date(2001, 4, 30), 4), (datetime.date(2001, 5, 31), 5), (datetime.date(2001, 6, 30), 6), (datetime.date(2001, 7, 31), 7), (datetime.date(2001, 8, 31), 8), (datetime.date(2001, 9, 30), 9), (datetime.date(2001, 10, 31), 10), (datetime.date(2001, 11, 30), 11), (datetime.date(2001, 12, 31), 12), ]) z = x.get_min_by_period('Y') self.assertEqual(z.get(), [ (datetime.date(2001, 12, 31), 1), ])