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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_queryset(self):
 """Get the list of items for this view. This must be an interable, and may be a queryset (in which qs-specific behavior will be enabled). See original in ``django.views.generic.list.MultipleObjectMixin``. """

        if self.queryset is not None:
            queryset = self.queryset
            if hasattr(queryset, '_clone'):
                queryset = queryset._clone()
        elif self.model is not None:
            queryset = self.model._default_manager.all()
        else:
            msg = '{0} must define ``queryset`` or ``model``'
            raise ImproperlyConfigured(msg.format(self.__class__.__name__))
        return queryset