ROT13 (Caesar Cipher)

In this ProgrammingPraxis challenge we have to build a simple Caesar Cipher with a special property, called rot13. ROT13 ("rotate by 13 places", sometimes hyphenated ROT-13) is a simple substitution cipher used in online forums as a means of hiding spoilers, punchlines, puzzle solutions, and offensive materials from the casual glance. ROT13 has been described as the "Usenet equivalent of a magazine printing the answer to a quiz upside down".ROT13 is an example of the Caesar cipher, developed in ancient Rome . In this article there is a small "functional" implementation for ROT13 written in python .