How to draw a chart in Google App Engine?

I wonder Google App Engine can return a chart ?

What I want is a statistical chart, is there a way for my app in Google App Engine to create a .png chart then return it to the browser ?

For instance when I click a url such as :

http://My_App.appspot.com/Show_App_Stats

It will show me a graphic chart.

Your best bet is to use the Google Visualization API.

A couple of years too late, but we now have Matplotlib available for Python 2.7 apps. (It's currently marked "experimental" so you shouldn't rely on it, but it is an option.)