Javascript swagger client, wait for spec to load

i'm trying to use https://github.com/swagger-api/swagger-js/. However one early issue i ran into is that i wish to use await to wait for the swaggerclient to finish loading the swagger specification.

Instead of having this long dot chain

new SwaggerClient({ spec })
  .then(client => client.apis.default.getUserById(...));

I would like do something like

async function getUserById(id) {
    const client = await new SwaggerClient({ spec });
    const default_api = client.apis.default;
    const user_with_id = await default_api.getUserById(...);
}

await getUserById(5)

But await does not seem to work with SwaggerClient my IDE warns me that "await has no effect" and when removed the code just says that default_api is undefined