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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 page_missing(request, page_name, revision_requested, protected=False):
 """Displayed if page or revision does not exist."""

    return Response(
        generate_template(
            "page_missing.html",
            page_name=page_name,
            revision_requested=revision_requested,
            protected=protected,
        ),
        status=404,
    )