Validate XML against DTD and/or XML Schema?

[Ravi Teja]

http://xmlstar.sourceforge.net/
Not Python, but just the tool for the job.

For Python, 4Suite has some validators. But parts of it were written in
C and might not be helpful if you want to look at the Python source
code. You might want to check
http://www.leuthe.homepage.t-online.de/minixsv/minixsv_overview.html
for a pure Python sample. The page says it is not complete though.