public static boolean verify(UserModel currentUser, CertificateMetadata edsMetadata) {
        logger.info("Trying to match via username and taxcode.");
        Map<String, List<String>> attrs = currentUser.getAttributes();
        String taxCode = edsMetadata.getTaxCode();
        if (null == taxCode) {
            logger.warn("Input taxCode {} is null", taxCode);
            return false;
        }
        if (attrs != null && !attrs.isEmpty()) {
            List<String> taxCodeValues = attrs.get(KeycloakAttributes.TAX_CODE);
            logger.info("Trying to match taxCode {} in values {}", taxCode, taxCodeValues);
            boolean isValidTaxCode = null == taxCodeValues ? false : taxCodeValues.contains(taxCode);
            if (isValidTaxCode) {
                return true;
            }
            logger.info("Not matched by this verifier.");
        }
        return false;
    }
@Test
    public void testVerifyWhenTaxCodeIsNull() {
        // Creating a mocked user model
        UserModel currentUser = Mockito.mock(UserModel.class);

        // Creating certificate metadata with null tax code
        CertificateMetadata edsMetadata = new CertificateMetadata().withTaxCode(null);

        // Test "verify" method
        boolean isValid = IndividualUserVerifierImpl.verify(currentUser, edsMetadata);

        assertEquals(false, isValid, "Expected verification to be false when tax code is null");
    }