models.py

        return _("Exam  ticket for %(participation)s in %(exam)s") % {
                "participation": self.participation,
                "exam": self.exam,
                }

    def clean(self):
        super().clean()

        try:
            if self.exam.course != self.participation.course:
                raise ValidationError(_("Participation and exam must live "
                        "in the same course"))
        except ObjectDoesNotExist:
            pass

# }}}

# vim: foldmethod=marker