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Implement and test the missing methods of the card validation class. The method for checking the expiration date is already implemented without errors. For a partial solution, it is enough to implement the 2 missing methods that check the properties of the card.

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Answer from AI

To implement missing methods in the card validation class, for example, you can add checks for the correctness of the card number and CVV.

Here's an example in Python:

class CardValidator:
    def __init__(self, number, expiry_date, cvv):
        self.number = number
        self.expiry_date = expiry_date
        self.cvv = cvv

    def validate_expiry_date(self):
        # Implementation
        pass

    def validate_number(self):
        # Check card number using Luhn's algorithm
        def luhn_checksum(card_number):
            def digits_of(n):
                return [int(d) for d in str(n)]
            digits = digits_of(card_number)
            odd_digits = digits[-1::-2]
            even_digits = digits[-2::-2]
            checksum = sum(odd_digits)
            for d in even_digits:
                checksum += sum(digits_of(d*2))
            return checksum % 10

        return luhn_checksum(self.number) == 0

    def validate_cvv(self):
        # CVV should be 3 or 4 digits
        return self.cvv.isdigit() and len(self.cvv) in (3, 4)

# Testing
validator = CardValidator('4532015112830366', '12/25', '123')
assert validator.validate_number() == True
assert validator.validate_cvv() == True

Thus, methods are implemented to check card properties, in addition to the already existing date check.

Implement and test the missing methods of the card… - sobes.tech