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

class AESCipher:
    def __init__(self,sec_param):
        self.sec_param = sec_param
        self.key = os.urandom(sec_param)
    #msg is string only
    def encrypt( self, msg):
        msg = pad(msg)
        tweak = Random.new().read( AES.block_size )
        cipher = AES.new(self.key, AES.MODE_CFB, tweak )
        return base64.b64encode(tweak + cipher.encrypt( msg ) )
    def decrypt(self, enc):
        enc = base64.b64decode(enc)
        tweak = enc[:16]
        cipher = AES.new(self.key, AES.MODE_CFB, tweak)
        return unpad(cipher.decrypt( enc[16:] ))

class BC(object):
def __init__(self, sec_param):
    self.sec_param = sec_param
def encrypt(self, message):
    return AESCipher(sec_param).encrypt(message)
def decrypt(self, encryption):
    return AESCipher(self.sec_param).decrypt(encryption)

msg = '100011010111110'
sec_param = 16
bc = BC(sec_param)
encr = bc.encrypt(msg)
decr = bc.decrypt(encr)

new_cipher = AESCipher(sec_param)
C = new_cipher.encrypt(msg)
D= new_cipher.decrypt(C)