Binary search tree implementation in Python

bst.py

import time
import random


class Node:
    def __init__(self, value, left, right):
        self.value = value
        self.left = left
        self.right = right


def insert(root, v):
    if root is None:
        root = Node(v, None, None)
    elif v < root.value:
        root.left = insert(root.left, v)
    else:
        root.right = insert(root.right, v)

    return root


def traverse(root):
    if root is None:
        return

    traverse(root.left)
    traverse(root.right)


if __name__ == "__main__":
    root = None
    SIZE = 2000000
    a = []

    print("Generating random array with %s values..." % SIZE)

    start = time.clock()

    for i in range(SIZE):
        a.append(random.randint(1, 10000))

    end = time.clock() - start

    print("Done. Took %s seconds\n" % end)
    print("Filling the tree with %s nodes..." % SIZE)

    start = time.clock()

    for i in range(SIZE):
        root = insert(root, a[i])

    end = time.clock() - start

    print("Done. Took %s seconds\n" % end)
    print("Traversing all %s nodes in tree..." % SIZE)

    start = time.clock()

    traverse(root)

    end = time.clock() - start

    print("Done. Took %s seconds\n" % end)