code: def resp_graph(dataframe, image_name, dir='./'):
      
      fig = pygal.TimeLine(x_title='Elapsed Time In Test (secs)',
                           y_title='Response Time (secs)',
                           x_label_rotation=25,
                           js=('scripts/pygal-tooltip.min.js',))
      fig.add('AVG', [(get_local_time(index), row['mean'] if pd.notnull(row['mean']) else None)
                      for index, row in dataframe.iterrows()])
      fig.add('90%', [(get_local_time(index), row['90%'] if pd.notnull(row['90%']) else None)
                      for index, row in dataframe.iterrows()])
      fig.add('80%', [(get_local_time(index), row['80%'] if pd.notnull(row['80%']) else None)
                      for index, row in dataframe.iterrows()])
      fig.render_to_file(filename=os.path.join(dir, image_name))
docs: Response time graph for bucketed data
  
      :param pandas.DataFrame dataframe: dataframe containing all data
      :param str image_name: the output file name
      :param str dir: the output directory
      :return: None