@staticmethod
def luhn_verify(numbers):
    """
        Custom verification for card numbers.
        :param str numbers: Fully qualified card numbers
        :return: True if passed, False otherwise.
        :rtype: bool
        """
    v_sum = 0
    num_digits = len(numbers)
    oddeven = num_digits & 1
    for count in range(0, num_digits):
        digit = int(numbers[count])
        if not count & 1 ^ oddeven:
            digit = digit * 2
        if digit > 9:
            digit = digit - 9
        v_sum += digit
    return v_sum % 10 == 0
