[Zope] maybe importing a Zope module

Heya, Is there a good reliable (documented?:) way for a product to tell if it's being imported by Zope or not? I've got a product which may or may not be imported by Zope. If it is, then it should load up the Zope-specific stuff and make it available - but if it's not, then it should ignore all that stuff (because it'll raise errors on trying to get DTMLFile and similar), and just present a simpler view of itself to the world. I can try and import as though it's a Zope module, and wrap that in try...excepts, but that seems dodgy - it'd mean I lose my nice tracebacks in the product control panel if I break the product at any time. Is there a better way? KevinL