import string
import math

def isPalindrome(s):
    """
    :type s: str
    :rtype: bool
    """
    # Create a translation table to remove uppercase letters and special characters
    # translation_table = str.maketrans("","", string.punctuation + string.whitespace)
    translation_table = ''.join(c.lower() if c.isupper() or c.isalnum() else '' for c in s if c.isalnum() or c in string.whitespace)
    # print(translation_table)
    if len(translation_table) == 2:
        if translation_table[0] == translation_table[1]:
            return True
        else:
            return False

    # Use the translation table to remove uppercase letters and special characters
    # upper_string = s.translate(translation_table)
    # lower_string = upper_string.lower()
    lower_string = translation_table

    half = len(lower_string)/2
    # Round the value down since middle value doesn't matter
    if len(lower_string)%2 != 0:
        halfdown = int(math.floor(half))
    else:
        halfdown = int(half)
    # print(halfup)
    # print(halfdown)
    first = []
    second = []
    print(lower_string)

    for i in range(halfdown):
        # print(i)
        # print(lower_string[i])
        first.append(lower_string[i])

    if len(lower_string)%2 != 0:
        for j in range(halfdown+1, len(lower_string)):
            second.insert(0, lower_string[j])

    else:
        for j in range(halfdown, len(lower_string)):
            second.insert(0, lower_string[j])

    print(first)
    print(second)
    if first == second:
        return True
    else:
        return False

print(isPalindrome("A man, a plan, a canal: Panama"))
print(isPalindrome("aa"))
print(isPalindrome("0P"))
print(isPalindrome("abba"))