def _get_helper(self, key, node: TreeNode) -> TreeNode:
output = None
if node.get_key() == key:
output = node
elif node.get_key() > key and node.get_left_child():
output = self._get_helper(key, node.get_left_child())
elif node.get_key() < key and node.get_right_child():
output = self._get_helper(key, node.get_right_child())
elif not node:
raise KeyError
return output
def _put_helper(self, key, value, node: TreeNode) -> None:
if key < node.get_key():
if node.get_left_child():
self._put_helper(key, value, node.get_left_child())
else:
node.set_left_child(TreeNode(key, value, parent=node))
elif key > node.get_key():
if node.get_right_child():
self._put_helper(key, value, node.get_right_child())
else:
node.set_right_child(TreeNode(key, value, parent=node))
else:
node.set_value(value)
