def distance_score(neighbors):
    """
    Calculates a distance-score for a peak given its neighbors.

    Parameters
    ----------
    neighbors : list of peaks
        The query peak's neighbors.

    Returns
    -------
    float
        The distance-score.

    Notes
    -----
    Lower distance-scores are better.
    """
    score = 0
    for neighbor in neighbors:
        score += neighbor['distance']
    return score / len(neighbors)
