In this task you will be given a string and you should find the longest substring that is a palindrome. A palindrome is a string that is the same backwards as it is forwards. If the shortest possible palindrome is length 1 you should return the first character.

[EX Q]: xrwxxxrrrxxxx
[EX A]: xxxrrrxxx

[EX Q]: itwwwwiiwtit
[EX A]: wwww

[EX Q]: yxuyyyxyyx
[EX A]:
yyxyy