public static ExtensibleLoadManagerImpl get(LoadManager loadManager) {
        if (!(loadManager instanceof ExtensibleLoadManagerWrapper loadManagerWrapper)) {
            throw new IllegalArgumentException("The load manager should be 'ExtensibleLoadManagerWrapper'.");
        }
        return loadManagerWrapper.get();
    }
@Test(timeOut = 30 * 1000)
    public void testCheckOwnershipPresentWithSystemNamespace() throws Exception {
        NamespaceBundle namespaceBundle =
                getBundleAsync(pulsar1, TopicName.get(NamespaceName.SYSTEM_NAMESPACE + "/test")).get();
        try {
            pulsar1.getNamespaceService().checkOwnershipPresent(namespaceBundle);
        } catch (Exception ex) {
            log.info("Got exception", ex);
            assertTrue(ex.getCause() instanceof UnsupportedOperationException);
        }
    }