Cannot find helmet

I am trying to had some custom headers, specifically crossOriginOpenerPolicy and crossOriginEmbedderPolicy, according to the docs I should be able to override helmet with a custom middleware. But when I try to import helmet, it can find it. (no problem with cors though)

serverSetup.ts:
import helmet from 'helmet';

export const serverMiddlewareFn = (middlewareConfig) => {
// Configure Helmet to set Cross-Origin-Opener-Policy and Cross-Origin-Embedder-Policy
middlewareConfig.set('helmet', helmet({
crossOriginOpenerPolicy: { policy: "same-origin" },
crossOriginEmbedderPolicy: { policy: "require-corp" }

}));

return middlewareConfig;
};

wasp.main:
... server: {
middlewareConfigFn: import { serverMiddlewareFn } from "@src/serverSetup"
},...