@Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;

        Card card = (Card) o;

        if (card_value != card.card_value) return false;
        return card_color == card.card_color;
    }

    @Override
    public int hashCode() {
        int result = card_value;
        result = 31 * result + (card_color != null ? card_color.hashCode() : 0);
        return result;
    }