new_contents: #!/usr/bin/python3.4
  import ulibrary
  import sys
  from uwindow import UWindow
  from gi.repository import Gtk
  
  
  class Usage(Exception):
      def __init__(self, msg):
          self.msg = msg
  
  
  def main():
      ulibrary.init()
  
      uwindow = UWindow()
      uwindow.connect("delete-event", Gtk.main.quit)
      uwindow.show_all()
      Gtk.main()
  
  if __name__ == "__main__":
      sys.exit(main())
  
subject: Implement main function