public static boolean isCreditCode(CharSequence creditCode) {
		if (false == isCreditCodeSimple(creditCode)) {
			return false;
		}

		final int parityBit = getParityBit(creditCode);
		if (parityBit < 0) {
			return false;
		}

		return creditCode.charAt(17) == BASE_CODE_ARRAY[parityBit];
	}
@Test
	public void isCreditCode() {
		String testCreditCode = "91310110666007217T";
		assertTrue(CreditCodeUtil.isCreditCode(testCreditCode));
	}