[Tutor] encrypt a file in Python3

[Mark Lawrence]

On 10/11/2012 05:54, kendy at kendy.org wrote:
> Hello!
>
> I want to encrypt a file, then decrypt it. I prefer to do it without adding any
> packages. I found
>
> http://eli.thegreenplace.net/2010/06/25/aes-encryption-of-files-in-python-with-pycrypto/
>
> which seems like a good approach. How can I get the import to work for python 3?

You install pycrypto on Python 3, which contradicts your stated preference.

> Here's what I get:
>
> $ uname -a
> Linux laptop 3.2.0-32-generic-pae #51-Ubuntu SMP Wed Sep 26 21:54:23 UTC 2012
> i686 i686 i386 GNU/Linux
> $ python3.2
> Python 3.2.3 (default, Sep 10 2012, 18:17:42)
> [GCC 4.6.3] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
>>>> import os, random, struct
>>>> from Crypto.Cipher import AES
> Traceback (most recent call last):
>    File "<stdin>", line 1, in <module>
> ImportError: No module named Crypto.Cipher
>>>> dir()
> ['__builtins__', '__doc__', '__name__', '__package__', 'os', 'random', 'struct']
>>>> import Crypto.Cipher
> Traceback (most recent call last):
>    File "<stdin>", line 1, in <module>
> ImportError: No module named Crypto.Cipher
>>>>
>
> Has Crypto.Cipher been renamed in Python 3? Is it supported yet? Python2.7 works
> fine.

Somebody (you?) has already installed pycrypto on 2.7.

>
> I saw so many "crypto" packages at http://pypi.python.org/pypi/ that I wouldn't
> know where to start. I want something simple. Do you have a suggestion?
>
> $ python2.7
> Python 2.7.3 (default, Aug  1 2012, 05:16:07)
> [GCC 4.6.3] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
>>>> import os, random, struct
>>>> from Crypto.Cipher import AES
>>>> dir()
> ['AES', '__builtins__', '__doc__', '__name__', '__package__', 'os', 'random',
> 'struct']
>>>>
>
> $ python2.7
> Python 2.7.3 (default, Aug  1 2012, 05:16:07)
> [GCC 4.6.3] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
>>>> import Crypto.Cipher
>>>> dir()
> ['Crypto', '__builtins__', '__doc__', '__name__', '__package__']
>>>>
>
> Thanks so much! I learn a lot from you guys!

You haven't seen my bill yet :)

>
> Ken
> kendy at kendy.org
>

-- 
Cheers.

Mark Lawrence.