def METHOD_NAME(self):
    # custom seasons with an invalid season raises an error?
    seasons = ("djf", "maj", "jja", "son")  # MAJ not a season!
    for func in (
        ccat.add_season,
        ccat.add_season_year,
        ccat.add_season_number,
    ):
        with self.assertRaises(ValueError):
            func(self.cube, "time", name="my_category", seasons=seasons)