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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 show_announcement_view(request):
 """ Unhide an announcement that was hidden by the logged-in user. announcements_hidden in the user model is the related_name for "users_hidden" in the announcement model. """

    if request.method == "POST":
        announcement_id = request.POST.get("announcement_id")
        if announcement_id:
            announcement = Announcement.objects.get(id=announcement_id)
            announcement.user_map.users_hidden.remove(request.user)
            announcement.user_map.save()
            return http.HttpResponse("Unhidden")
        raise http.Http404
    else:
        return http.HttpResponseNotAllowed(["POST"], "HTTP 405: METHOD NOT ALLOWED")