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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 decompress(self, value):
 """ Return the primary key value for the ``Select`` widget if the given recurrence rule exists in the queryset. """

        if value:
            try:
                pk = self.queryset.get(recurrence_rule=value).pk
            except self.queryset.model.DoesNotExist:
                pk = None
            return [pk, None, value]
        return [None, None, None]