def verify_credit_card(number):
    """
    Assignment 3
    """
    if len(number) <= 16:
        doubling = []
        for num in number[0:len(number) - 1]:
            if int(num) * 2 > 9:
                result = int(num) * 2
                doubling.append(result[0] + result[1])
            else:
                doubling.append(int(num) * 2)
        all_sum_number = sum(doubling)
        check_sum = sum(doubling) * 9
        if number[-1] == str(check_sum)[-1]:
            return number
        else:
            return False
    else:
        return False