def quantile(feature, bins):
    """Equal frequency bin, take a uniform distribution of the sample size.
    
    Args:
        feature: pd.Series, model feature values.
        bins: int, split bins of feature.
    Returns:
        the list of split threshold of feature.
    """
    t = feature.sort_values().values
    w = round(len(t)/bins)
    return [t[w*i] for i in range(bins)]+[feature.max()]