6line AC python
\n\n\n        def isSymmetric(self, root):\n            def isSym(L,R):\n                if not L and not R: return True\n                if L and R and L.val =
\n\n\n        def isSymmetric(self, root):\n            def isSym(L,R):\n                if not L and not R: return True\n                if L and R and L.val == R.val: \n                    return isSym(L.left, R.right) and isSym(L.right, R.left)\n                return False\n            return isSym(root, root)
['Python']