stealth screen scraping with python?

[different.engine at gmail.com]

Folks:

I am screen scraping a large volume of data from Yahoo Finance each
evening, and parsing with Beautiful Soup.

I was wondering if anyone could give me some pointers on how to make
it less obvious to Yahoo that this is what I am doing, as I fear that
they probably monitor for this type of activity, and will soon ban my
IP.

-DE