'Return a list of courses that need scores computed.'

def _get_course_keys(self, options):

    courses_mode = get_mutually_exclusive_required_option(options, u'courses', u'all_courses', u'from_settings')
    if (courses_mode == u'all_courses'):
        course_keys = [course.id for course in modulestore().get_course_summaries()]
    elif (courses_mode == u'courses'):
        course_keys = parse_course_keys(options[u'courses'])
    else:
        course_keys = parse_course_keys(self._latest_settings().course_ids.split())
    return course_keys
