code: def barv(d, plt, title=None, rotation='vertical'):
      
      labels = sorted(d, key=d.get, reverse=True)
      index = range(len(labels))
      plt.xticks(index, labels, rotation=rotation)
      plt.bar(index, [d[v] for v in labels])
  
      if title is not None:
          plt.title(title)
docs: A convenience function for plotting a vertical bar plot from a Counter