def set_newsletter_state(self, state):
if IPossibleNewsletter.providedBy(self.context):
ifaces = interface.directlyProvidedBy(self.context)
if state and not INewsletterEnhanced.providedBy(self.context):
interface.alsoProvides(self.context, INewsletterEnhanced)
elif not state and INewsletterEnhanced in ifaces:
interface.directlyProvides(self.context, ifaces - INewsletterEnhanced)
def get_newsletter_state(self):
if IPossibleNewsletter.providedBy(self.context):
return INewsletterEnhanced.providedBy(self.context)
return False