Version 1.0.0: Initial release with Stack, Queue, and Linked List classes. Version 2.0.0: Add Binary Tree and LRU Cache classes. Version 2.1.0: Implement add_after_key and add_before_key to Linked List and LRU Cache classes. Version 2.2.0: Implement Heap class. Version 2.3.0: Add additional methods to Heap class. Version 2.4.0: Add Priority Queue class. Version 2.5.0: Add Graph, Directed Graph, Weighted Graph, and Weighted Directed Graph classes.