class List(BaseModel):
    """
    List of items.
    """
    items: list[str]

vector_store = RedisVectorStore(
    custom_schema={} # some complex schema I skip
    redis_url=f"redis://{REDIS_HOST}:{REDIS_PORT}",
)

llm = OpenAI(model="gpt-3.5-turbo-0125", temperature=0.0, api_key=OPENAI_API_KEY)
embeddings_model = OpenAIEmbedding(api_key=OPENAI_API_KEY)

Settings.embed_model = embeddings_model
Settings.llm = llm

index = VectorStoreIndex.from_vector_store(vector_store=vector_store)
pydantic_query_engine = index.as_query_engine(output_cls=List, response_mode=ResponseMode.TREE_SUMMARIZE)
query: PydanticResponse = pydantic_query_engine.query("List 5 keywords describing the text.")
print(query.response.json())