Python | Leetcode Python题解之第226题翻转二叉树

题目：

题解：

class Solution:
    def invertTree(self, root: TreeNode) -> TreeNode:
        if not root:
            return root
        
        left = self.invertTree(root.left)
        right = self.invertTree(root.right)
        root.left, root.right = right, left
        return root