'Adds a unit to the subsection, which
should not affect a persisted subsection grade.'

def _change_subsection_structure(self):

    self.studio_course_outline.visit()
    subsection = self.studio_course_outline.section(self.SECTION_NAME).subsection(self.SUBSECTION_NAME)
    subsection.expand_subsection()
    subsection.add_unit()
    self.studio_course_outline.wait_for_ajax()
    subsection.publish()
