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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 get_queryset(self):
 """The queryset is over-ridden to show only plug events in which the strain matches the breeding strain."""

        self.strain = get_object_or_404(Strain, Strain_slug__iexact=self.kwargs['slug'])
        return PlugEvents.objects.filter(Breeding__Strain=self.strain)