compatibility issues between python2 and python3

[lucaclivio]

I want be able to encrypt something with python2 and decrypt it with python3 and viceversa, I was expecting to see the encrypted text independent from the version of python used but something went wrong. Let's take this script:

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import sys,os,os.path,hashlib,pprp,pprp.config,base64

def trans(text):
    return text.encode('utf-8') if sys.version_info[0] >= 3 else text

passphrase = trans('passwordò')
salt = trans('salt')
key_size = 32
data = trans("papà")
print(data.decode('utf-8') if sys.version_info[0] >= 3 else data)

key = pprp.pbkdf2(passphrase, salt, key_size)

# Encrypt.
sg = pprp.data_source_gen(data)
eg = pprp.rjindael_encrypt_gen(key, sg)
encrypted = pprp.encrypt_sink(eg)
print(base64.b64encode(encrypted))
# Decrypt.
sg = pprp.data_source_gen(encrypted)
dg = pprp.rjindael_decrypt_gen(key, sg)
decrypted = pprp.decrypt_sink(dg)
print(decrypted.decode('utf-8') if sys.version_info[0] >= 3 else decrypted)

This piece of software is taken from your example2 test code. I simply substituted the encoding with ASCII with UTF-8 to be able to cope with different encoding, but nothing changes with ASCII.
If you run this script with python2 or python3 the script works but differently: the two produce different encoded strings, so the two are not compatible with each other

luca@ictvt224:~$ python test_pprp.py 
papà
xQoR0CIEWbHhliKukN1CrA==
papà
luca@ictvt224:~$ python3 test_pprp.py 
papà
b'jK8D0w7bXKt3o11uJlyeGQ=='
papà

How am I wrong?