isSymmetric

# Definition for a binary tree node.
class node:
     def __init__(self, val=0, left=None, right=None):
         self.val = val
         self.left = left
         self.right = right
class Solution:
        def isSymmetric(self, root):
            if not root:
                return True

            def isMirror(node1, node2):
                if node1 == None and node2 == None:
                    return True
                
                if node1 == None or node2 == None:
                    return False
                
                
                return node1.val == node2.val and \
                isMirror(node1.left, node2.right) and\
                isMirror(node1.right, node2.left)
            return isMirror(root.left, root.right)
root = node(1)
root.left = node(2)
root.right = node(2)
root.left.left = node(3)
root.left.right = node(4)
root.right.left = node(4)
root.right.right = node(3)

myVar = Solution()
myVar.isSymmetric(root)