code: def get_or_create_calendar_for_object(self, obj, distinction='', name=None):
          
          try:
              return self.get_calendar_for_object(obj, distinction)
          except Calendar.DoesNotExist:
              if name is None:
                  calendar = self.model(name=str(obj))
              else:
                  calendar = self.model(name=name)
              calendar.slug = slugify(calendar.name)
              calendar.save()
              calendar.create_relation(obj, distinction)
              return calendar
docs: >>> user = User(username="jeremy")
          >>> user.save()
          >>> calendar = Calendar.objects.get_or_create_calendar_for_object(user, name = "Jeremy's Calendar")
          >>> calendar.name
          "Jeremy's Calendar"