I'm using SubQuestionQueryEngine.from_

from llama_index.core import get_response_synthesizer

synthesizer = get_response_synthesizer(llm=llm, response_mode="compact", streaming=True)

query_engine = SubQuestionQueryEngine.from_defaults(..., response_synthesizer=synthesizer)

response = query_engine.query("..")
for token in response.response_gen:
  print(token, end="", flush=True)