old_contents: # pylint: disable=E1101
  """
  Run these tests @ Devstack:
      paver test_system -s lms --test_id=lms/djangoapps/gradebook/tests.py
  """
  from datetime import datetime
  import uuid
  
  from django.conf import settings
  from django.contrib.auth.models import User
  from django.test.utils import override_settings
  
  from xmodule.modulestore.tests.factories import CourseFactory, ItemFactory
  from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase, mixed_store_config
  
  from util.signals import course_deleted
  
  from student.models import CourseAccessRole
  
  MODULESTORE_CONFIG = mixed_store_config(settings.COMMON_TEST_DATA_ROOT, {}, include_xml=False)
  
  
  @override_settings(MODULESTORE=MODULESTORE_CONFIG)
  class InstructorReceiversTests(ModuleStoreTestCase):
      """ Test suite for signal receivers """
  
      def setUp(self):
          super(InstructorReceiversTests, self).setUp()
          # Create a course to work with
          self.course = CourseFactory.create(
              start=datetime(2014, 6, 16, 14, 30),
              end=datetime(2020, 1, 16)
          )
          test_data = '<html>{}</html>'.format(str(uuid.uuid4()))
  
          self.chapter = ItemFactory.create(
              category="chapter",
              parent_location=self.course.location,
              data=test_data,
              due=datetime(2014, 5, 16, 14, 30),
              display_name="Overview"
          )
  
          self.user = User.objects.create(email='testuser@edx.org', username='testuser', password='testpassword', is_active=True)
  
      def test_receiver_on_course_deleted(self):
          """
          Test the workflow
          """
          # Set up the data to be removed
          CourseAccessRole.objects.create(course_id=self.course.id, user=self.user, role='instructor')
  
          # Emit the signal
          course_deleted.send(sender=None, course_key=self.course.id)
  
          # Validate that the course references were removed
          self.assertEqual(CourseAccessRole.objects.filter(course_id=self.course.id).count(), 0)
  
new_contents: # pylint: disable=E1101
  """
  Run these tests @ Devstack:
      paver test_system -s lms --test_id=lms/djangoapps/gradebook/tests.py
  """
  from datetime import datetime
  import uuid
  
  from django.conf import settings
  from django.contrib.auth.models import User
  from django.test.utils import override_settings
  
  from xmodule.modulestore.tests.factories import CourseFactory, ItemFactory
  from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase, mixed_store_config
  
  from util.signals import course_deleted
  
  from student.models import CourseAccessRole
  
  MODULESTORE_CONFIG = mixed_store_config(settings.COMMON_TEST_DATA_ROOT, {}, include_xml=False)
  
  
  @override_settings(MODULESTORE=MODULESTORE_CONFIG)
  class InstructorReceiversTests(ModuleStoreTestCase):
      """ Test suite for signal receivers """
  
      def setUp(self):
          super(InstructorReceiversTests, self).setUp()
          # Create a course to work with
          self.course = CourseFactory.create(
              start=datetime(2014, 6, 16, 14, 30),
              end=datetime(2020, 1, 16)
          )
          test_data = '<html>{}</html>'.format(str(uuid.uuid4()))
  
          self.chapter = ItemFactory.create(
              category="chapter",
              parent_location=self.course.location,
              data=test_data,
              due=datetime(2014, 5, 16, 14, 30),
              display_name="Overview"
          )
  
      def test_receiver_on_course_deleted(self):
          """
          Test the workflow
          """
          # Set up the data to be removed
          CourseAccessRole.objects.create(course_id=self.course.id, user=self.user, role='instructor')
  
          # Emit the signal
          course_deleted.send(sender=None, course_key=self.course.id)
  
          # Validate that the course references were removed
          self.assertEqual(CourseAccessRole.objects.filter(course_id=self.course.id).count(), 0)
  
subject: Remove username conflict from instructor receivers test.