Validating Credit Card Numbers

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    My regex-only implementation:

    from re import match
    p = '^(?=[456])(?!.*(.)-?\\1-?\\1-?\\1)(\\d{4}-?){3}\\d{4}$'
    
    for _ in range(int(input())):
        n = input()
        print('Valid' if match(p, n) else 'Invalid')