def _overall_stats(label, tuples):
    """
    Computes overall accuracy; returns in 'Settings'-friendly format.

    Args: tuples([(int, int)]) Each entry is (# correct, # total) label (str)
        What to call this

    Returns: (str, str) key, val of settings column to add
    """
    n_correct = sum(tp[0] for tp in tuples)
    n_total = sum(tp[1] for tp in tuples)
    return 'OVERALL %s acc' % (label), '%d/%d (%0.2f%%)' % (
        n_correct, n_total, (n_correct*100.0)/n_total)