条件分岐

def get_day(day_number):
    match day_number:
        case 0:
            return "日曜日"
        case 1:
            return "月曜日"
        case 2:
            return "火曜日"
        case 3:
            return "水曜日"
        case 4:
            return "木曜日"
        case 5:
            return "金曜日"
        case 6:
            return "土曜日"
        case _:
            return "不正な値です"