new_contents: #!/usr/bin/env python3
  # -*- coding: utf-8 -*-
  
  import pyglet
  
  window = pyglet.window.Window()
  
  label = pyglet.text.Label('Hello, world',
                            font_name='Times New Roman',
                            font_size=36,
                            x=window.width//2, y=window.height//2,
                            anchor_x='center', anchor_y='center')
  
  @window.event
  def on_draw():
      window.clear()
      label.draw()
  
  pyglet.app.run()
  
subject: Add a snippet.