declare module 'event-source-polyfill'
// import { OutgoingHttpHeaders } from 'http'

// declare module 'event-source-polyfill' {
//   interface EventSourceInitPolyfill extends EventSourceInit {
//     headers?: OutgoingHttpHeaders
//   }
//   export const EventSourcePolyfill: {
//     prototype: EventSource
//     new (
//       url: string,
//       eventSourceInitDict?: EventSourceInitPolyfill
//     ): EventSource
//     readonly CLOSED: number
//     readonly CONNECTING: number
//     readonly OPEN: number
//   }
// }
