It probably looks something like this:
export function getEventStreamFromElement<U extends Event = Event>(type: string, element: Element, eventListenerOptions?: AddEventListenerOptions): ObservableWithMotionOperators<U>;
export function getEventStreamFromElement<K extends keyof GlobalEventHandlersEventMap>(type: K, element: Element, eventListenerOptions?: AddEventListenerOptions): ObservableWithMotionOperators<GlobalEventHandlersEventMap[K]>;