video.py

import pyglet
player = pyglet.media.Player()
source = pyglet.media.StreamingSource()
media = pyglet.media.load('example-video.mp4')
player.queue(media)
player.play()
window = pyglet.window.Window()
while player.source and player.source.video_format:
    pyglet.clock.tick(poll=True)
    window.clear()
    tex = player.get_texture()
    if tex is None:
        break
    tex.blit(0, 0)
    window.flip()
    window.dispatch_events()