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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, queryset=None):
 """ Returns a queryset for this request. Arguments: queryset: Optional root-level queryset. """

        serializer = self.get_serializer()
        return getattr(self, 'queryset', serializer.Meta.model.objects.all())