human
I found an interesting problem on https://leetcode.com/problems/valid-palindrome/:
Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases.

Note: For the purpose of this problem, we define empty string as valid palindrome.

Example 1:

Input: "A man, a plan, a canal: Panama"
Output: true

Example 2:

Input: "race a car"
Output: false

I tried it in Python, but could not do it. Can you solve it?

Give me a Python program to determine if it is a palindrome, considering only alphanumeric characters and ignoring cases?
assistant
#Here is Python program to determine if it is a palindrome, considering only alphanumeric characters and ignoring cases.

class Solution:
     def isPalindrome(self, s):
         """
         :type s: str
         :rtype: bool
         """
         cleanlist = [c for c in s.lower() if c.isalnum()]
         return cleanlist == cleanlist[::-1]