new_contents: from django.conf import settings
  
  def is_test_database():
      """
      Return whether we're using test database. Can be used to determine if we're
      running tests.
      """
  
      # This is hacky, but fact we're running tests is determined by _create_test_db call.
      # We'll assume usage of it if assigned to settings.DATABASE_NAME
  
      if settings.TEST_DATABASE_NAME:
          test_database_name = settings.TEST_DATABASE_NAME
      else:
          from django.db import TEST_DATABASE_PREFIX
          test_database_name = TEST_DATABASE_PREFIX + settings.DATABASE_NAME
  
      return settings.DATABASE_NAME == test_database_name
  
subject: Add utils.is_test_database