"""
Exercise 6.3. A palindrome is a word that is spelled the same backward and forward, like “noon”
and “redivider”. Recursively, a word is a palindrome if the first and last letters are the same and the
middle is a palindrome.

my second attempt:
    new concept: 'abc'[-100,300] is a valid syntax. And we get an empty string
"""

def is_palindrome(word):
    """ empty string is a palindrome so is a character """
    if len(word) <= 1:
        return True

    if word[0] == word[-1]:
        return is_palindrome(middle(word))
    else:
        return False

def middle(word):
    """Returns all but the first and last characters of a string."""
    return word[1:-1]

print(': ' + str(is_palindrome(''))) #True
print('j: ' + str(is_palindrome('j'))) #True
print('kk: ' + str(is_palindrome('kk'))) #True
print('noon: ' + str(is_palindrome('noon'))) #True
print('abc: ' + str(is_palindrome('abc'))) #False
print('redivider: ' + str(is_palindrome('redivider'))) #True