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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 retrieve(self, request, project, pk=None):
 """ GET method implementation for detail view of ``push`` """

        try:
            push = Push.objects.get(repository__name=project,
                                    id=pk)
            serializer = PushSerializer(push)
            return Response(serializer.data)
        except Push.DoesNotExist:
            return Response("No push with id: {0}".format(pk),
                            status=HTTP_404_NOT_FOUND)