How to use the parfive.utils.run_in_thread function in parfive

def _start_loop(self, loop):
        # Setup asyncio loops
        if not loop:
            aio_pool = ThreadPoolExecutor(1)
            self.loop = asyncio.new_event_loop()
            self.run_until_complete = partial(run_in_thread, aio_pool, self.loop)
        else:
            self.loop = loop
            self.run_until_complete = self.loop.run_until_complete

        asyncio.set_event_loop(self.loop)

        # Setup queues
        self.http_queue = asyncio.Queue(loop=self.loop)
        self.http_tokens = asyncio.Queue(maxsize=self.max_conn, loop=self.loop)
        self.ftp_queue = asyncio.Queue(loop=self.loop)
        self.ftp_tokens = asyncio.Queue(maxsize=self.max_conn, loop=self.loop)
        for i in range(self.max_conn):
            self.http_tokens.put_nowait(Token(i + 1))
            self.ftp_tokens.put_nowait(Token(i + 1))