<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def display_grid_scores(grid_scores, top=None):
 """Helper function to format a report on a grid of scores"""

    grid_scores = sorted(grid_scores, key=lambda x: x[1], reverse=True)
    if top is not None:
        grid_scores = grid_scores[:top]
        
    # Compute a threshold for staring models with overlapping stderr:
    _, best_mean, best_scores = grid_scores[0]
    threshold = best_mean - 2 * sem(best_scores)
    
    for params, mean_score, scores in grid_scores:
        append_star = mean_score + 2 * sem(scores) > threshold
        print(display_scores(params, scores, append_star=append_star))