How is it possible that the outer class is able to access the private instance variables of the inner class? In this example, how does the
instance have access to the private field
in the outer class method? Here are both classes:
public class StringsLinkedList {
    public void add(String value) {
        Node newNode = new Node();
        newNode.value = "5"; // How is this possible given `.value` is private??

    public static class Node {
        private Node prev;
        private String value;
        private Node next;