old_contents: #!/usr/bin/env python
  
  #-*- coding: utf-8 -*-
  '''
  Created on Jun 03, 2017
  
  @author ujnzxw <ujnzxw@gmail.com>
  '''
  
  import random
  from   manage_earth    import EarthManager
  from   manage_momentum import MomentumdashManager
  from   config          import display_model
  
  
  def main():
  
      obj_list = [ EarthManager, MomentumdashManager ]
  
      if display_model == "random":
          index = random.randint(0, len(obj_list)-1)
          print index
          obj_list[index]().run()
  
      elif display_model == "earth":
          EarthManager().run()
  
      elif display_model == "momentumdash":
          MomentumdashManager().run()
  
      else:
          EarthManager().run()
  
  if __name__ == "__main__":
      main()
  
new_contents: #!/usr/bin/env python
  
  #-*- coding: utf-8 -*-
  '''
  Created on Jun 03, 2017
  
  @author ujnzxw <ujnzxw@gmail.com>
  '''
  
  import random
  from   manage_earth    import EarthManager
  from   manage_momentum import MomentumdashManager
  from   config          import display_model
  
  
  def main():
  
      obj_list = [ EarthManager, MomentumdashManager ]
  
      if display_model == "random":
          index = random.randint(0, len(obj_list)-1)
          obj_list[index]().run()
  
      elif display_model == "earth":
          EarthManager().run()
  
      elif display_model == "momentumdash":
          MomentumdashManager().run()
  
      else:
          EarthManager().run()
  
  if __name__ == "__main__":
      main()
  
subject: remove print