import string
# word = "fabricate"
# print ''.join([chr(ord(letter)-3) for letter in word])
# string.ascii_lowercase - 'abcdefghijklmnopqrstuvwxyz'
letters = string.ascii_lowercase
offset = 3
while True:
word = raw_input("Enter word").lower()
reenter = False
for s in word:
if s not in
letters:
print
"INVALID. Entry must be all alpha characters!"
reenter =
True
break
if not reenter:
break
print "Entered word: %s" % word
print "Offset word: %s" %
''.join([letters[letters.index(letter)-offset] for
letter in word])