new_contents: 
  import plot
  import model
  
  import sys
  import numpy as np
  import os.path as path
  import matplotlib.pyplot as plt
  
  group_size = model.load(path.realpath(sys.argv[1]))['group_size']
  sizes = np.unique(group_size)
  
  print("%7s | %3s" % ("size", "count"))
  
  for size in sizes:
      print("%7d | %3d" % (size, np.sum(group_size == size)))
  
subject: add ASCII groupsize histogram