text: from django.db import models
  from basecrowd.models import AbstractCrowdTaskGroup
  from basecrowd.models import AbstractCrowdTask
  from basecrowd.models import AbstractCrowdWorker
  from basecrowd.models import AbstractCrowdWorkerAssignment
  
  # Inherited crowd models for the interface.
  # No need for special subclasses, we use the base implementations.
  class CrowdTaskGroup(AbstractCrowdTaskGroup): pass
  class CrowdTask(AbstractCrowdTask): pass
  class CrowdWorker(AbstractCrowdWorker): pass
  class CrowdWorkerAssignment(AbstractCrowdWorkerAssignment): pass
  