classSolution:definorderTraversal(self,root:Optional[TreeNode])->List[int]:self.res=[]defintree(node):ifnotnode:returnNoneintree(node.left)self.res.append(node.val)intree(node.right)intree(root)returnself.resclassSolution:definorderTraversal(self,root:Optional[TreeNode])->List[int]:self.res=[]defintree(node):ifnotnode:returnNoneintree(node.left)self.res.append(node.val)intree(node.right)intree(root)returnself.res