AES is available out of the box, see example usage below. Though I would be interested to compare to native CommonCrypto as a benchmark...

import base64
import hashlib
from Crypto import Random
from Crypto.Cipher import AES

class AESCipher(object):

    def __init__(self, key): 
        self.bs = 32
        self.key = hashlib.sha256(key.encode()).digest()

    def encrypt(self, raw):
        raw = self._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[:AES.block_size]
        cipher = AES.new(self.key, AES.MODE_CBC, iv)
        return self._unpad(cipher.decrypt(enc[AES.block_size:])).decode('utf-8')

    def _pad(self, s):
        return s + (self.bs - len(s) % self.bs) * chr(self.bs - len(s) % self.bs)

    @staticmethod
    def _unpad(s):
        return s[:-ord(s[len(s)-1:])]

if __name__ == '__main__':  # pragma: no cover
    aes = AESCipher('this is my key')
    plaintext = 'hello, I am very happy to meet you!'
    print 'plain  =', plaintext
    ciphertext = aes.encrypt(plaintext)
    print 'cipher =', ciphertext
    plaintwo = aes.decrypt(ciphertext)
    print 'plain2 =', plaintwo
    

I'm new to Pythonista (it's awesome!) and was looking for a example using ui.NavigationView. There was a simple example in the UI Tutorial at https://github.com/humberry/ui-tutorial that demonstrated the basics and was quite helpful. What I wanted to do was have a controller class for each view and a separate controller to handle the transitions. I also wanted to be able to try out the individual interfaces as I storyboard the app. So here it is... if you have ideas on how to make this better as an example let me know:

https://github.com/jadeblaquiere/controller-example