def METHOD_NAME(df, metric, prefix):
    num_xticks = len(df)
    plt = df.plot(kind="bar", 
                    title=f"{METRICS[metric]}", 
                    ylabel=METRICS[metric],
                    grid=True,
                    figsize=(max(num_xticks*0.5, 4), 6,),
        )
    plt.figure.savefig(f"{prefix}/bar_{metric}.png")