Function create_realtime_session 

pub fn create_realtime_session<C, Fut, B, E>(
    client: C,
    request: &RealtimeSessionCreateRequest,
) -> CreateRealtimeSession<Fut, B, E> 
where
    C: FnOnce(Request<String>) -> Fut,
    Fut: Future<Output = Result<Response<B>, E>>,
    B: Body,

Create session