rot.py

#!/usr/bin/env python3

# rot(num), 1-26

import sys

num = int(sys.argv[1])
decode_string = sys.argv[2]

def rot_alpha(n):
    from string import ascii_lowercase as lc, ascii_uppercase as uc
    lookup = str.maketrans(lc + uc, lc[n:] + lc[:n] + uc[n:] + uc[:n])
    return lambda s: s.translate(lookup)


decoded = rot_alpha(num)(decode_string) # Uryyb Jbeyq
print("[+] decoded: ", decoded)