How to use the fdk.constants.is_py37 function in fdk

def get_delayed_module_init_class():
    if constants.is_py37():
        return Python37DelayedImport
    else:
        return Python35plusDelayedImport

websocket_max_size=websocket_max_size,
        websocket_max_queue=websocket_max_queue,
        websocket_read_limit=websocket_read_limit,
        websocket_write_limit=websocket_write_limit,
        state=state,
        debug=debug,
    )

    create_server_kwargs = dict(
        ssl=ssl,
        reuse_port=reuse_port,
        sock=sock,
        backlog=backlog,
    )

    if constants.is_py37():
        create_server_kwargs.update(
            start_serving=False
        )

    server_coroutine = loop.create_server(
        server, **create_server_kwargs
    )

    # Instead of pulling time at the end of every request,
    # pull it once per minute
    loop.call_soon(partial(update_current_time, loop))

    if run_async:
        return server_coroutine

    try:

def start():
        pid = os.getpid()
        try:
            logger.info("Starting worker [%s]", pid)
            if constants.is_py37():
                loop.run_until_complete(http_server.serve_forever())
            else:
                loop.run_forever()
        finally:
            http_server.close()
            loop.run_until_complete(http_server.wait_closed())
            loop.run_until_complete(loop.shutdown_asyncgens())
            loop.close()

def start_serving():
        if constants.is_py37():
            loop.run_until_complete(http_server.start_serving())