How can I run a python script through a webserver and return results to javascript?
Put your Python script in your CGI directory and use the cgi and json modules in your script to read AJAX from post/get params. Of course you can do a system call from PHP to run a Python script, but I can't think of a good reason why you would.
I want to take results from a web page, sent from dom as json through ajax, then send this data to a python script, run it, then return the new results back as json. I was told a php script running gearman would be a good bet, but I'm still not sure how that would work.