How to access Bindings inside custom functions of an RPC Worker?

import { WorkerEntrypoint } from "cloudflare:workers";

export default class MyRPCWorker extends WorkerEntrypoint {
  async fetch(req: Request, env: Env) { console.log("env as the second argument is valid in the fetch handler"); }

  async customFunction(param1: string) { console.log("I need to access the env of the current RPC worker here when calling this method from another worker using Service Bindings...") }
}