How Do I Suppress or Disable Warnings in reSTructuredText?

Question

I'm working on a CMS in Python that uses reStructuredText (via docutils) to format content. Alot of my content is imported from other sources and usually comes in the form of unformatted text documents. reST works great for this because it makes everything look pretty sane by default.

One problem I am having, however, is that I get warnings dumped to stderr on my webserver and injected into my page content. For example, I get warnings like the following on my web page:

System Message: WARNING/2 (, line 296); backlink

My question is: How do I suppress, disable, or otherwise re-direct these warnings?

Ideally, I'd love to write these out to a log file, but if someone can just tell me how to turn off the warnings from being injected into my content then that would be perfect.

The code that's responsible for parsing the reST into HTML:

from docutils import core
import reSTpygments

def reST2HTML( str ):
    parts = core.publish_parts(
                          source = str,
                          writer_name = 'html')
    return parts['body_pre_docinfo'] + parts['fragment']