The whole practical.
Not just the answer.

To construct a binary search tree from a set of integer keysand print them in ascending order using in-order traversal.

A binary search tree is a rooted tree in which every node'sleft subtree holds smaller keys and its right subtree larger.The invariant holds at every node, so an in-order walk sorts.

1. 1. Start with an empty root pointer.
2. 2. For each key, descend left if smaller, right if larger.
3. 3. Insert at the first empty position reached.
4. 4. Traverse: left subtree, node, right subtree.

class Node:    def __init__(self, key):        self.key = key        self.left = self.right = Nonedef insert(root, key):    if root is None: return Node(key)    return root