def return_top(scores, metric, x=None):
    """

    Args:
      scores(pandas.DataFrame): pandas.DataFrame with scores
      metric(str): string value for what score is desired
      ("Growth Score", "Value Score", "Momentum Score", "Score")
      x(int, optional): integer number of top stocks to return (Default value = None)

    Returns:
      pandas.DataFrame: top x number of stocks by score as pandas.DataFrame

    """
    if x is not None:
        return scores.nlargest(x, [metric])
    else:
        return scores.nlargest(len(scores), [metric])