Binary Search Tree operations with Python

BSTOPS.py

class Node:
    def __init__(self, key=None, left=None, right=None, parent=None, value=1):
        self.key = key
        self.left = left
        self.right = right
        self.parent = parent
        self.value = value
        
def insert(key, value, node, parent=None):
    if not node:
        print(value)
        return Node(key=key, value=value, parent=parent)
    if key == node.key:
        return Node(key=key, left=node.left, right=node.right, parent=node.parent, value=value)
    if key < node.key:
        return Node(key=node.key, left=insert(key,2*node.value, node.left, node), right=node.right, value=node.value)
    return Node(key=node.key, left=node.left, right=insert(key, 2*node.value+1, node.right, node), value=node.value)

def find_sucessor(node):
    if not node:
        return
    if node.left:
        return find_sucessor(node.left)
    return node

def delete(key, node):
    if not node or not key:
        return
    if key < node.key:
        return Node(key=node.key, left=delete(key, node.left), right=node.right, parent=node.parent, value=node.value)
    if key > node.key:
        return Node(key=node.key, left=node.left, right=delete(key, node.right), parent=node.parent, value=node.value)
    if key == node.key:
        print(node.value)
        if node.left and node.right:
            sucessor = find_sucessor(node.right)
            return Node(key=sucessor.key, left=node.left, right=delete(sucessor.key, node.right), parent=node.parent, value=node.value)
        if node.left:
            return Node(key=node.left.key, left=node.left.left, right=node.left.right, parent=node.parent, value=node.value)
        if node.right:
            return Node(key=node.right.key, left=node.right.left, right=node.right.right, parent=node.parent, value=node.value)
        return None
        
def update_values(tree, parent=None):
    if not tree:
        return tree
    if parent:
        if parent.left and tree.key == parent.left.key:
            tree.value = parent.value*2
            return Node(key=tree.key, left=update_values(tree.left, tree), right=update_values(tree.right, tree), parent=parent, value=tree.value)
        if parent.right and tree.key == parent.right.key:
            tree.value = 2*parent.value+1
            return Node(key=tree.key, left=update_values(tree.left, tree), right=update_values(tree.right, tree), parent=parent, value=tree.value)           
    return Node(key=tree.key, left=update_values(tree.left, tree), right=update_values(tree.right, tree), parent=parent, value=1)

def read_tree(tree):
    if not tree:
        return
    print(tree.key, tree.value)
    if tree.left:
        read_tree(tree.left)
    if tree.right:
        read_tree(tree.right)

n_op = int(input())

tree = None

for n in range(n_op):
    op_i = input()
    
    op = op_i.split()[0]
    key = int(op_i.split()[1])
    
    if op == 'i':
        tree = insert(key, 1, tree)
    if op == 'd':
        tree = delete(key, tree)
        tree = update_values(tree)

read_tree(tree)