def METHOD_NAME(self):
    data = [
            ('2', 2), ('5', 5), ('8', 8),
            ('A', 1), ('10', 10), ('J', 10),
            ('Q', 10), ('K', 10)]
    for variant, (card, value) in enumerate(data, 1):
        with self.subTest(f'variation #{variant}', input=card, output=value):
            error_msg = f'Expected {value} as the value of {card}.'
            self.assertEqual(value_of_card(card), value, msg=error_msg)