# Learn Tree Traversal by Building a Binary Search Tree - Step 35

I’m not sure what I am missing, but I am having trouble returning the node.right to replace the left child at the end of the code…

``````def _insert(self, node, key):
if node is None:
return TreeNode(key)
if key < node.key:
node.left = self._insert(node.left, key)
elif key > node.key:
node.right = self._insert(node.right, key)
return node

def search(self, key):
return self._search(self.root, key)

def _search(self, node, key):
if node is None or node.key == key:
return node
if key < node.key:
return self._search(node.left, key)
return self._search(node.right, key)

def delete(self, key):
self.root = self._delete(self.root, key)

def _delete(self, node, key):
if node is None:
return node
if key < node.key:
node.left = self._delete(node.left, key)
elif key > node.key:
node.right = self._delete(node.right, key)
``````

# User Editable Region

``````    else:
if node.left == None:
return node.right
``````

# User Editable Region

``````    else:
if node.left == None:
return node.right
``````

# User Editable Region

``````

User Agent is: <code>Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36</code>

### Challenge Information:
Learn Tree Traversal by Building a Binary Search Tree - Step 35
https://www.freecodecamp.org/learn/scientific-computing-with-python/learn-tree-traversal-by-building-a-binary-search-tree/step-35``````

You cannot use `==` to compare with `None`. You should use the `is` operator.

1 Like

Oh my gosh. I was so focused on my return line
Thank you…

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