Comment 20 for bug 901498

except that zope interfaces hates the world.

  File "/home/robertc/source/launchpad/lp-branches/working/lib/lp/services/twistedsupport/loggingsupport.py", line 65, in set_up_oops_reporting
    directlyProvides(oops_observer, log.ILogObserver)
  File "/home/robertc/source/launchpad/lp-sourcedeps/eggs/zope.interface-3.5.2-py2.6-linux-i686.egg/zope/interface/declarations.py", line 861, in directlyProvides
    object.__provides__ = Provides(cls, *interfaces)
exceptions.AttributeError: 'instancemethod' object has no attribute '__provides__'
...
so the example code in twisted is misleading (doing an emit method is incompatible with using actual classes). Worse they don't implement the needed interface themselves!