method MyLinkedList.prototype.addBeforeimport { MyLinkedList } from "https://deno.land/x/masx200_leetcode_test@7.6.0/lfu-cache/MyLinkedList.ts"; addBefore(next_node: DoublyLinkedList<T>, new_node: DoublyLinkedList<T>): voidParametersnext_node: DoublyLinkedList<T>new_node: DoublyLinkedList<T>Returnsvoid