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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):
 """ Retrieve a bug-job-map entry. pk is a composite key in the form bug_id-job_id """

        job_id, bug_id = map(int, pk.split("-"))
        job = Job.objects.get(repository__name=project, id=job_id)
        try:
            bug_job_map = BugJobMap.objects.get(job=job, bug_id=bug_id)
            serializer = BugJobMapSerializer(bug_job_map)

            return Response(serializer.data)
        except BugJobMap.DoesNotExist:
            return Response("Object not found", status=HTTP_404_NOT_FOUND)