old_contents: import os
  import sys
  sys.path.insert(0, os.path.abspath('../'))
  
  import pyglet
  import pyglet_gui.theme
  
  # define a theme
  theme = pyglet_gui.theme.Theme(os.path.join(sys.path[0], 'theme'), override={
      "gui_color": [64, 128, 255, 255],
      "font_size": 12
  })
  
  window = pyglet.window.Window(640, 480, resizable=True, vsync=True)
  batch = pyglet.graphics.Batch()
  bg_group = pyglet.graphics.OrderedGroup(0)
  fg_group = pyglet.graphics.OrderedGroup(1)
  fps = pyglet.clock.ClockDisplay()
  
  @window.event
  def on_draw():
      window.clear()
      batch.draw()
      fps.draw()
  
  # register event to update pyglet-gui
  window.register_event_type('on_update')
  
  
  def update(dt):
      window.dispatch_event('on_update', dt)
  pyglet.clock.schedule(update)
  
new_contents: import os
  import sys
  sys.path.insert(0, os.path.abspath('../'))
  
  import pyglet
  import pyglet_gui.theme
  
  # define a theme
  theme = pyglet_gui.theme.Theme(os.path.join(sys.path[0], 'theme'))
  
  window = pyglet.window.Window(640, 480, resizable=True, vsync=True)
  batch = pyglet.graphics.Batch()
  bg_group = pyglet.graphics.OrderedGroup(0)
  fg_group = pyglet.graphics.OrderedGroup(1)
  fps = pyglet.clock.ClockDisplay()
  
  @window.event
  def on_draw():
      window.clear()
      batch.draw()
      fps.draw()
  
  # register event to update pyglet-gui
  window.register_event_type('on_update')
  
  
  def update(dt):
      window.dispatch_event('on_update', dt)
  pyglet.clock.schedule(update)
  
subject: remove the theme override in setup.py