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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 shipping_countries(request):
 """ Get all shipping countries """

    queryset = models.Country.objects.exclude(shippingrate=None)
    serializer = serializers.CountrySerializer(queryset, many=True)
    return Response(data=serializer.data, status=status.HTTP_200_OK)