The background=True argument was introduced in Dash 2. chat_models import ChatOpenAI from langchain. That signals to the compiler that this method contains an await statement; it contains. Return type. Async function as callback. inheritable_callbacks ( Optional[Callbacks], optional) – The inheritable callbacks. add_endRequest. manager. When the value of this. string RaiseCallbackEvent(string eventArgument) This server-side method is called when the client-side asynchronous method is called. If exception is raised, then success = False, result=exception_raised and if it is not raised, then success = True, result=value_returned. " + ". I had a similar issue installing langchain with all integrations via pip install langchain [all]. I am pretty new with async programming and python in general but I want to implement an asynchronous function inside a state machine. The core idea of the library is that we can “chain” together different components to create more advanced use cases around LLMs. It will be executed when the action you specify occurs, rather like the way that an event handler is called to handle a user's interaction with an application.