HTML parser/reformatter/filter wanted

[Alexander Staubo]

I'm looking for a piece of Python code that can filter HTML and tie up 
unclosed tags.

By way of explanation: I'm building a bulletin-board-ish solution where 
users should be able to post HTMl-formatted submissions; I only want to 
enable a subset of HTML (eg., <b>, <i> and so forth), plus I want to make 
sure text-level tags are ended correctly. I could sit down and write a 
smaller HTML parser, but I don't want to reinvent wheels if I can just 
grab this stuff off the shelf.

-- 
Alexander Staubo             http://www.mop.no/~alex/
"He could open a tin of sardines with his teeth, strike a Swan Vestas 
on his chin, rope steers, drive a steam locomotive and hum all the 
works of Gilbert and Sullivan without becoming confused or breaking 
down in tears."
--Robert Rankin, _The Book of Ultimate Truths_