def METHOD_NAME(self, assume_zero_enabled):
    """
    Creates a zero course grade and ensures that null scores aren't included in the section problem scores.
    """
    with patch('lms.djangoapps.grades.subsection_grade.get_score', return_value=None):
        course_data = CourseData(self.request.user, structure=self.course_structure)
        chapter_grades = ZeroCourseGrade(self.request.user, course_data).chapter_grades
        for chapter in chapter_grades:
            assert {} != chapter_grades[chapter]['sections']
            for section in chapter_grades[chapter]['sections']:
                assert {} == section.problem_scores