text: import django_filters
  from django.db.models import lookups as django_db_lookups
  
  from courses import defines as courses_defines
  from courses import models as courses_models
  from grades import models as grades_models
  
  
  class ExamFilters(django_filters.FilterSet):
      course_id = django_filters.UUIDFilter(
          field_name="__".join((
              grades_models.Exam.course_group.field.name,
              courses_models.CourseGroup.course_instance.field.name,
              courses_models.CourseInstance.course_id.field.attname,
          )),
          distinct=True,
      )
  
      course_code = django_filters.CharFilter(
          field_name="__".join((
              grades_models.Exam.course_group.field.name,
              courses_models.CourseGroup.course_instance.field.name,
              courses_models.CourseInstance.course.field.name,
              courses_models.Course.course_code.field.name,
          )),
          lookup_expr=django_db_lookups.Exact.lookup_name,
          distinct=True,
          min_length=courses_defines.COURSE_CODE_LENGTH,
          max_length=courses_defines.COURSE_CODE_LENGTH,
      )
  
      course_group_id = django_filters.UUIDFilter()
  
      course_instance_id = django_filters.UUIDFilter(
          field_name="__".join((
              grades_models.Exam.course_group.field.name,
              courses_models.CourseGroup.course_instance_id.field.attname,
          )),
      )
  
      course_group_name = django_filters.CharFilter(
          field_name="__".join((
              grades_models.Exam.course_group.field.name,
              courses_models.CourseGroup.course_group_name.field.name,
          )),
      )
  
      moed = django_filters.NumberFilter()
  