Suma el valor de blackjack de cada carta y devuelve el conteo total. Las cartas 2 a 6 suman 1, 7 a 9 suman 0, y 10, J, Q, K y A restan 1.
count([5, 9, 10, 3, "J", "A", 4, 8, 5]) ➞ 1
count(["A", "A", "K", "Q", "Q", "J"]) ➞ -6
count(["A", 5, 5, 2, 6, 2, 3, 8, 9, 7]) ➞ 50.2, 3, 4, 5, 6, 7, 8, 9, 10, "J", "Q", "K", "A".