code: async def _create_upstream_applications(self):
          
          loop = asyncio.get_event_loop()
          for steam_name, ApplicationsCls in self.applications.items():
              application = ApplicationsCls(self.scope)
              upstream_queue = asyncio.Queue()
              self.application_streams[steam_name] = upstream_queue
              self.application_futures[steam_name] = loop.create_task(
                  application(
                      upstream_queue.get,
                      partial(self.dispatch_downstream, steam_name=steam_name)
                  )
              )
docs: Create the upstream applications.