I’m happy to help with if something is wrong on the platform. But outside of it, there could be number of reasons the code might not work, as in your case, you are using updated libraries, and things might have moved around in the source code. I encourage you to find the solution and share it here so that others can benefit from it as well if they are using the same library versions as you.
from langchain.embeddings import OpenAIEmbeddings # or other embeddings
# Create the embedding model
embedding_model = OpenAIEmbeddings() # You can use any supported embedding model here
index = VectorstoreIndexCreator(
vectorstore_cls=DocArrayInMemorySearch,
embedding=embedding_model
).from_loaders([loader])