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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 question_default_loader(self, pk):
 """Load a Question from the database."""

        try:
            obj = Question.objects.get(pk=pk)
        except Question.DoesNotExist:
            return None
        else:
            self.question_default_add_related_pks(obj)
            return obj