USE PYTHON LANGUAGE

def maximum(self) -> Optional[int]: ""Return the maximum number in this BST, or None if this BST is empty. Hint: Review the BST property to ensure you aren't making unnecessary recursive calLs >>> BinarySearchTree(None).maximun() True is None # Empty BST >> BinarysearchTree(10).maximum() 10 >>> bst = BinarySearchTree(7) >>> left BinarySearchTree (3) >>> left._left BinarySearchTree(3) >>> left-right = BinarySearchTree(5) >right - BinarySearchTree (11) >>right._left-BinarySearchTree(9) >>> right-right = BinarySearchTree(13) >bst. left- left bst._right - right >bst.maximum) 13 pass