This has gota be simple and im just missing it.
index = VectorStoreIndex(storage_context=storage_context, service_context=service_context)
ValueError: One of nodes or index_struct must be provided.
All the samples show building the vectorStoreIndex.from_documents, but what's the right way to have take an existing already built index and simply create the object so that you can do other things like,
index.as_query_engine()