Equivalent functionality to Google Charts API from python ? (Venn Diagrams also needed!)

is there any library (for C or python) that I can use to get roughly the same functionality as I can get from Google Charts ?

I specifically need the pie diagrams (standard), multi-dataset-pie-diagrams (not-so-standard), and venn diagrams (rare)开发者_运维问答...

http://pygooglechart.slowchop.com/ is a Python wrapper for the Google Charts API. Also see Pretty graphs and charts in Python