Traceback (innermost last):
  Module ZPublisher.Publish, line 119, in publish
  Module ZPublisher.mapply, line 88, in mapply
  Module ZPublisher.Publish, line 42, in call_object
  Module Products.GenericSetup.tool, line 726, in manage_createSnapshot
  Module Products.GenericSetup.tool, line 375, in createSnapshot
  Module Products.ATContentTypes.exportimport.atcttool, line 164, in exportATCTTool
  Module Products.GenericSetup.utils, line 765, in exportObjects
  Module Products.GenericSetup.utils, line 528, in _exportBody
  Module Products.ATContentTypes.exportimport.atcttool, line 27, in _exportNode
  Module Products.GenericSetup.utils, line 656, in _extractProperties
  Module OFS.PropertyManager, line 151, in getProperty
AttributeError: image_types