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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_metric(run_id, metric_id):
 """ Get a specific Sacred metric from the database. Returns a JSON response or HTTP 404 if not found. Issue: https://github.com/chovanecm/sacredboard/issues/58 """

    data = current_app.config["data"]  # type: DataStorage
    dao = data.get_metrics_dao()
    metric = dao.get(run_id, metric_id)

    return Response(render_template(
        "api/metric.js",
        run_id=metric["run_id"],
        metric_id=metric["metric_id"],
        name=metric["name"],
        steps=metric["steps"],
        timestamps=metric["timestamps"],
        values=metric["values"]),
        mimetype="application/json")