Encrypt & Decrypt using PyCrypto AES 256 From http://stackoverflow.com/a/12525165/119849

AESCipher.py

#!/usr/bin/env python

import base64

from Crypto import Random
from Crypto.Cipher import AES

BS = 16
pad = lambda s: s + (BS - len(s) % BS) * chr(BS - len(s) % BS)
unpad = lambda s : s[0:-ord(s[-1])]


class AESCipher:

    def __init__( self, key ):
        self.key = key

    def encrypt( self, raw ):
        raw = pad(raw)
        iv = Random.new().read( AES.block_size )
        cipher = AES.new( self.key, AES.MODE_CBC, iv )
        return base64.b64encode( iv + cipher.encrypt( raw ) )

    def decrypt( self, enc ):
        enc = base64.b64decode(enc)
        iv = enc[:16]
        cipher = AES.new(self.key, AES.MODE_CBC, iv )
        return unpad(cipher.decrypt( enc[16:] ))


cipher = AESCipher('mysecretpassword')
encrypted = cipher.encrypt('Secret Message A')
decrypted = cipher.decrypt(encrypted)
print encrypted
print decrypted

requirements.txt

pycrypto==2.6.1

This only works because the 'mysecretpassword' is 16 bytes. If it were a different (not dividable by 16) amount of bytes you'd get
"ValueError: AES key must be either 16, 24, or 32 bytes long"
To avoid this the key may be hashed:
self.key = hashlib.sha256(key.encode('utf-8')).digest()

Very minor changes to make it python 3 compatible https://gist.github.com/mguezuraga/257a662a51dcde53a267e838e4d387cd

def pad(s):
    return s + (BS - len(s) % BS) * chr(BS - len(s) % BS)


def unpad(s):
    return s[0:-s[-1]]

lambda removed(pep 8 support)
ord removed(python 3 support)

In Python 3 using the modifications of Craz1k0ek it still doesn't work with Unicode. For example the input Hello, 你好 raises ValueError: Input strings must be a multiple of 16 in length

Edit: found a working version: https://stackoverflow.com/a/44212550

i think this is aes 128, we have a standard blocksize of 16 bytes (128bit)

i can't seem to find how to do aes256

Please provide the JAVA code equivalent to above which is in python.

i think this is aes 128, we have a standard blocksize of 16 bytes (128bit)

Key size decides if it is aes 256 or 128, block size is 16 in both of em