# open the file with the encoded message and make it into a string

messy_file = open('mess.txt')

messy_string = messy_file.read()

messy_file.close()

# create a dictionary to keep count of each character occurance

unique_letters = set(messy_string)

letter_counter = {}

for unique in unique_letters:

counter = 0

for letter in messy_string:

if letter == unique:

counter += 1

letter_counter[unique] = counter

# add the rarest characters to a new string

rare_characters = ""

for key, value in letter_counter.items():

if value == 1:

rare_characters += key

print(rare_characters)

# Using a scrabble word finder, the word is "equality"