why it append one more letter after decode?

[Ho Yeung Lee]

if run these function to decode in python interactive console,
it can decode correct, 

but when run with a big project, it append a letter Y


On Monday, October 30, 2017 at 9:48:36 AM UTC+8, Ho Yeung Lee wrote:
> def leftrotate(l, n):
>     return l[n:] + l[:n]
> 
> def rightrotate(l, n):
>     return l[-n:] + l[:-n]
> 
> def encode(s, k, kk):
>     l = [ord(i) for i in s]
>     return leftrotate(''.join([chr(i + k) for i in l]), kk)
> 
> def decode(s, k, kk):
>     l = [ord(i) for i in rightrotate(s, kk)]
>     return ''.join([chr(i - k) for i in l])
> 
> 
> yesterday i add above code and run it with batch file 
> it can decode a correct password
> 
> then i install cx_freeze to produce executable file
> 
> but today when i run it, i see the source of encrypted password is correct
> but the decode one, it append one more letter Y at the end of string
> 
> why?
> is cx_freeze change the source python 2.7?