AttributeError: module 'pyglet.gl' has no attribute 'glColor3f'

1. Run this code: https://github.com/viblo/pymunk/blob/master/examples/spiderweb.py
2. Getting error:

Traceback (most recent call last):
  File "C:/pymunk_proj/spiderweb.py", line 184, in <module>
    pyglet.app.run()
  File "C:\Program Files\Python38\lib\site-packages\pyglet\app\__init__.py", line 107, in run
    event_loop.run(interval)
  File "C:\Program Files\Python38\lib\site-packages\pyglet\app\base.py", line 183, in run
    timeout = self.idle()
  File "C:\Program Files\Python38\lib\site-packages\pyglet\app\base.py", line 244, in idle
    self.clock.call_scheduled_functions(dt)
  File "C:\Program Files\Python38\lib\site-packages\pyglet\clock.py", line 274, in call_scheduled_functions
    item.func(now - item.last_ts, *item.args, **item.kwargs)
  File "C:\Program Files\Python38\lib\site-packages\pyglet\app\base.py", line 154, in _redraw_windows
    window.dispatch_event('on_draw')
  File "C:\Program Files\Python38\lib\site-packages\pyglet\window\__init__.py", line 1327, in dispatch_event
    super().dispatch_event(*args)
  File "C:\Program Files\Python38\lib\site-packages\pyglet\event.py", line 415, in dispatch_event
    if handler(*args):
  File "C:/pymunk_proj/spiderweb.py", line 158, in on_draw
    pyglet.gl.glColor3f(1, 0, 1)
AttributeError: module 'pyglet.gl' has no attribute 'glColor3f'
Error in sys.excepthook:

Original exception was:

OS: Win 10 Python: 3.8 Pymunk: 6.2.0 Pyglet: 2.0.dev9