在下面的Laravel5模型中，findByIdAndCourseOrFail方法应该是静态的吗？classSectionextendsModel{//shouldthismethodbestatic?publicfunctionfindByIdAndCourseOrFail($id,$courseId){$result=$this->where('id',$id)->where('course_id',$courseId)->first();if(!is_null($result)){return$result;}throw(newModelNotFoundException())-