Palindrome

A palindrome is a word or phrase that reads the same forwards as it does backwards.

Challenge

Write a python function to determine if a given string is a palindrome. Only consider letters (A-Z)

Input

String to evaluate.

Output

Boolean Value.

For e.g.

palindrome_checker('aIbohPhoBiA') True

and

palindrome_checker('hello_world') False

Test the palindrome_checker using the 50+ Palindrome Sentences found here at https://www.scarymommy.com/palindrome-sentences/ .