xor42.py

#!/usr/bin/env python3                                                          
from __future__ import print_function                                           
import sys                                                                      
                                                                                
try:                                                                            
    input = sys.argv[1]                                                         
                                                                                
    if not input:                                                               
        print("No!", file=sys.stderr)                                           
        sys.exit(1)                                                             
except:                                                                         
    print("Usage: " + sys.argv[0] + " <string>", file=sys.stderr)               
    sys.exit(1)                                                                 
                                                                                
print("In: " + input)                                                           
output = []                                                                     
for c in list(input):                                                           
    magic = ord(c) ^ 42                                                         
    print(ord(c), chr(ord(c)), magic, chr(magic))                               
    output.append(chr(magic))                                                   
                                                                                
print(''.join(output))