'Set the grading policy for the first subsection in the specified section.
If a section index is not provided, 0 is assumed.'

def _set_policy_for_subsection(self, policy, section=0):

    with self._logged_in_session(staff=True):
        self.studio_course_outline.visit()
        modal = self.studio_course_outline.section_at(section).subsection_at(0).edit()
        modal.policy = policy
        modal.save()
