public static String checksum(Client client) {
        String s = buildUniqueString(client);
        if (s == null) {
            return "0";
        }
        return MD5Utils.md5Hex(s, Constants.ENCODE);
    }
@Test
    void testChecksum0() {
        for (int i = 0; i < 3; i++) {
            assertEquals("2a3f62f84a4b6f2a979434276d546ac1", DistroUtils.checksum(client0));
        }
    }