Write a function that will check whether the permutation of an input string is a palindrome. Bonus points for a solution that is efficient and/or that uses _only_ built-in language functions. Deem yourself **brilliant** if you can come up with a version that does not use _any_ function whatsoever.
# Example 
  `madam` -> True   
  `adamm` -> True   
  `junk`  -> False  
## Hint 
The brute force approach would be to generate _all_ the permutations of the string and check each one of them whether it is a palindrome. However, an optimized approach will not require this at all.
from functools import reduce
from operator import xor

def permute_a_palindrome(input_): 
    return len(reduce(xor, [set(c) for c in input_], set())) <= 1
from functools import reduce
from operator import xor

def permute_a_palindrome(input_): 
    return len(reduce(xor, [set(c) for c in input_], set())) <= 1