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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 revisions( request, slug, template_name='wakawaka/revisions.html', extra_context=None ):
 """ Displays the list of all revisions for a specific WikiPage """

    queryset = WikiPage.objects.all()
    page = get_object_or_404(queryset, slug=slug)

    template_context = {'page': page}
    template_context.update(extra_context or {})
    return render(request, template_name, template_context)