text: from matplotlib import pyplot as plt
  
  
  plt.figure()
  
  # primes_queue.py on job C
  xs = [1, 2, 4, 8]
  ys = [83, 73, 90, 90]
  #plt.scatter(xs, ys, marker='x')
  plt.plot(xs, ys, '--x', label="Using Queues")
  plt.annotate("1 child process via Queues", (xs[0], ys[0]))
  
  # primes_queue_less_work - not sure there's any point showing this?
  #xs = [1, 2, 4, 8]
  #ys = [57, 36, 48, 49]
  #plt.scatter(xs, ys, marker='v')
  
  xs = [1]
  ys = [25]
  #plt.scatter(xs, ys, marker='o')
  plt.plot(xs, ys, '-o', label="No queue")
  plt.annotate("No queue", (xs[0], ys[0]))
  plt.xlim(0.5, 8.5)
  plt.ylim(0, 100)
  
  plt.title("The overhead of Queues on lightweight tasks")
  plt.ylabel("Seconds (smaller is better)")
  plt.xlabel("Number of processes")
  plt.legend(loc="center right")
  
  plt.draw()
  plt.tight_layout()
  plt.savefig("multiprocessing_serial_vs_queue_times.png")
  