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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 set_experiment_winner(experiment):
 """Mark an alternative as the winner of the experiment."""

    redis = _get_redis_connection()
    experiment = Experiment.find(redis, experiment)
    if experiment:
        alternative_name = request.form.get('alternative')
        alternative = Alternative(redis, alternative_name, experiment.name)
        if alternative.name in experiment.alternative_names:
            experiment.winner = alternative.name
    return redirect(url_for('.index'))