code: public CMAAsset unPublish(CMAAsset asset) {
      assertNotNull(asset, "asset");
  
      final String assetId = getResourceIdOrThrow(asset, "asset");
      final String spaceId = getSpaceIdOrThrow(asset, "asset");
      final String environmentId = asset.getEnvironmentId();
  
      return service.unPublish(spaceId, environmentId, assetId).blockingFirst();
    }
docs: Un-Publish an Asset.
  
  @param asset Asset
  @return {@link CMAAsset} result instance
  @throws IllegalArgumentException if asset is null.
  @throws IllegalArgumentException if asset's id is not set.
  @throws IllegalArgumentException if asset's space id is not set.