Given the head of a singly linked list, return true if it is a palindrome or false otherwise. Example 1:Input: head = [1,2,2,1]Output: trueExample 2:Input: head = [1,2]Output: false Constraints:The number of nodes in the list is in the range [1, 105].0 Follow up: Could you do it in O(n) time and O(1) space? code by python:# Definition for singly-linked list.# class ListNode:# def __init__(..