public static boolean isOpReturn(Script script) {
        List<ScriptChunk> chunks = script.chunks();
        return chunks.size() > 0 && chunks.get(0).equalsOpCode(ScriptOpCodes.OP_RETURN);
    }
@Test
    public void testCreateOpReturnScript() {
        assertTrue(ScriptPattern.isOpReturn(
                ScriptBuilder.createOpReturnScript(new byte[10])
        ));
    }