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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 on_log(request, page_name):
 """Show the list of recent changes."""

    page = Page.query.filter_by(name=page_name).first()
    if page is None:
        return page_missing(request, page_name, False)
    return Response(generate_template("action_log.html", page=page))