# filename leetcode.py
from leetcode_test import TreeNode

class Solution:
    def isSymmetric(self, root: TreeNode) -> bool:
        def symmetric(left, right):
            if not left and not right:
                return True
            if not left or not right:
                return False
            return (
                left.val == right.val
                and symmetric(left.left, right.right)
                and symmetric(left.right, right.left)
            )
        if not root:
            return True
        return symmetric(root.left, root.right)

def test():
    tree = TreeNode.create([1,2,3,4,5])
    assert Solution().isSymmetric(tree)

pytest leetcode.py

pip install git+https://github.com/Twotiger/leetcode_test.git