Define a class DoublyLinkedBag that implements the ADT bag by using a doubly linked

chain, as shown in Figure $3-11.$ Use the inner class of nodes that Exercise $12$ defines.

Then write a program that adequately demonstrates your implementation.

Exercise$-12$: In a doubly linked chain, each node can reference the previous node as well as

the next node. Figure $3-11$ shows a doubly linked chain and its head reference. Define a

class to represent a node in a doubly linked chain. Write the class as an inner class of a

class that implements the ADT bag. You can omit set and get methods.

A doubly linked chain for Exercises $!14,$ and $15,$ and Project $7($DAta structure question$)$