[Zope] DTML for getting content type of files in a folder?

Hi, I have some folders which have arbitrary number of files of varying content types. A DTML Method is supposed to list them, and give them custom icons based on content-type. I can use getContentType() directly on a file object, but I can't figure out how to use it on a sequence item. What is the proper way of doing this? Here is not-working code for what I'd like to do: <dtml-in "objectIds(['File'])"> <dtml-if "sequence-item.getContentType()=='text/css'"> <dtml-var css_icon> </dtml-if> </dtml-in> Any suggestions? Thanks, Joe