A string is an almost-palindrome if, by changing only one character, you can make it a palindrome. Create a function that returns True if a string is an almost-palindrome and False otherwise.
almost_palindrome("abcdcbg") ➞ True
# Transformed to "abcdcba" by changing "g" to "a".
almost_palindrome("abccia") ➞ True
# Transformed to "abccba" by changing "i" to "b".
almost_palindrome("abcdaaa") ➞ False
# Can't be transformed to a palindrome in exactly 1 turn.
almost_palindrome("1234312") ➞ False
Return False if the string is already a palindrome.