XML parsing in python: expaterror not well-formed

[zoomie999]

I'm using Python's xml.etree.ElementTree to do some XML parsing on a file. However, I get this error mid-way through the document:\[code\]xml.parsers.expat.ExpatError: not well-formed (invalid token): line X, column Y\[/code\]So I go to line X, column Y in vim and I see an ampersand (&) with red background highlighting. What does this mean? Also the two characters preceeding it are >>, so maybe there's something special about ">>&"? Anyone know how to fix this? Thanks.