Python palindrome program not working

Question

I've written a simple program in python which checks if the sentence is palindrome. But I can't figure out why isn't it working. The results is always False. Does anyone knows what's wrong?

def isPalindrome(word):
    # Removes all spaces, and lowercase the word.
    word = word.strip().lower()
    word = word.replace(" ", "")

    # If the length of the word is less than 1, means its a palindrome
    if (len(word) <= 1):
        return True

    # Compares the first and the last character of the word.
    # If it is the same, calls the function again with the same word,
    # without its first and last characters. If its not the same, its
    # not palindrome
    else:
        if word[0] == word[-1]:
            isPalindrome(word[1:-1])
        else:
            return False


sentence = input("Enter a sentence: \n")

if (isPalindrome(sentence)):
    print("The sentence %s is palindrome." % sentence)
else:
    print("The sentence %s is NOT palindrome" % sentence)

Answer 1

You aren't returning the result of the function.

replace :

if word[0] == word[-1]:
    isPalindrome(word[1:-1])

with

if word[0] == word[-1]:
    return isPalindrome(word[1:-1])