new_contents: # -*- coding: utf-8 -*-
  """
  Utilities for converting RGB values from the Tableau web site to hex values
  and generating demo plots
  """
  
  import numpy as np
  import matplotlib.pyplot as plt
  
  
  tableau20 = [(31, 119, 180), (174, 199, 232), (255, 127, 14), (255, 187, 120),
               (44, 160, 44), (152, 223, 138), (214, 39, 40), (255, 152, 150),
               (148, 103, 189), (197, 176, 213), (140, 86, 75), (196, 156, 148),
               (227, 119, 194), (247, 182, 210), (127, 127, 127),
               (199, 199, 199), (188, 189, 34), (219, 219, 141), (23, 190, 207),
               (158, 218, 229)]
  
  tableau10 = [(31, 119, 180), (255, 127, 14), (44, 160, 44), (214, 39, 40),
               (148, 103, 189), (140, 86, 75), (227, 119, 194), (127, 127, 127),
               (188, 189, 34), (23, 190, 207)]
  
  tableau_cb10 = [(0, 107, 164), (255, 128, 14), (171, 171, 171), (89, 89, 89),
                  (95, 158, 209), (200, 82, 0), (137, 137, 137), (162, 200, 236),
                  (255, 188, 121), (207, 207, 207)]
  
  
  def make_plot(N):
      """ plot N sine waves"""
      x = np.linspace(0, 2*np.pi, 255)
      for i in range(N):
          plt.plot(x, np.sin(x - i*np.pi/N))
  
      plt.show()
  
  
  def rgb_to_hex(rgb):
      """convert rgb tuple to hex"""
      print('{:02x}{:02x}{:02x}'.format(*rgb))
  
  
  def convert_list(colors):
      """convert list or rgb colors into hex"""
      for rgb in colors:
          rgb_to_hex(rgb)
  
  
  if __name__ == '__main__':
      plt.style.use('fivethirtyeight')
      plt.style.use('./tableau_cb10.mplstyle')
      make_plot(10)
  #    convert_list(tableau_cb10)
  
subject: add utils.py which shows RGB values and a function to convert to hex