Encrypting a short string?

[erikcw]

On Feb 11, 3:07 pm, marek.ro... at wp.pl wrote:
> erikcw napisal(a):
>
>
>
> > Hi,
>
> > I'm trying to devise a scheme to encrypt/obfuscate a short string that
> > basically contains the user's username and record number from the
> > database.  I'm using this encrypted string to identify emails from a
> > user. (the string will be in the subject line of the email).
>
> > I'm trying to figure out which approach I should use to encrypt the
> > data.  The string will be less than 20 characters long, and I'd like
> > the encrypted version to be about the same size.
>
> > I tried DES in the Crypto module, but the cipher text was to long to
> > be usable in this case.
>
> > Any suggestions?
>
> > Thanks!
>
> How about:
>
> >>> hashlib.sha256("john.sm... at example.com|2937267834").hexdigest()[:20]
>
> Regards,
> Marek

Thanks Marek,

But that can't be reversed, right?  I'd like to be able to decrypt the
data instead of having to store the hash in my database...