import uuid


def next_thread_id():
  return str(uuid.uuid4())


async def PER_REQ_CONFIG_MODIFIER(config, request):
  body = await request.json()
  return {
    "configurable": {
      "thread_id":
        body
        .get("config", {})
        .get("configurable", {})
        .get("thread_id", None) or next_thread_id()
    }
  }