If you're going to keep credentials in plaintext on disk, at least make them keys and stop dicking about with expect.
From the code in the link it looks like for basic sftp tasks paramiko is simple enough that you really don't need a wrapper for it, but I'll take the single-page google code README for pysftp over paramiko's docs [2] any day
[1] http://code.google.com/p/pysftp/ [2] http://www.lag.net/paramiko/docs/
In short, this can be solved with proper access restrictions and full key-based authentication, and nothing but bash and scp/sftp.
The paramiko module is the "right" way of doing this in Python, and probably only appropriate if you need to integrate SFTP transactions into a larger, longer-running application.
Edit: I might add the use of a password in a command line argument is not advisable because it will get logged everywhere and show up in things like top, etc. Probably better to hardcode it or put it in a 0600 file.
[1]: http://en.wikipedia.org/wiki/Expect (In fact, there is a complete example for automating SFTP right in the article).
