The factory function, card(), is a mixture of two very common Factory design patterns:

• An if-elif sequence
• A mapping

For the sake of simplicity, it can be better to focus on just one of these techniques rather than on both.

We can always replace a mapping with elif conditions. (Yes, always. The reverse is not true though; transforming elif conditions to a mapping can be challenging.)

The following is a Card factory without a mapping:

def card3(rank: int, suit: Suit) -> Card:
    if rank == 1:
        return AceCard("A", suit)
    elif 2 <= rank < 11:
        return Card(str(rank), suit)
    elif rank == 11:
        return FaceCard("J", suit)
    elif rank == 12:
        return FaceCard("Q", suit)
    elif rank == 13:
        return FaceCard("K", suit)
    else:
        raise Exception("Rank out of range")

We rewrote the card() factory function. The mapping was transformed into additional elif clauses. This function has the advantage that it is more consistent than the previous version.