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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 save_model(model, output_file):
 """Save model to output_file, if given"""

    if not output_file:
        return

    with open(output_file, 'wb') as f:
        pickle.dump(model, f)
    print("Saved model to file '{}'.".format(output_file))