AttributeError: 'NoneType' object has no attribute 'set_current'

[Pegasus133]

Is there a following error when running python bin/interactive.py --scenario simple.py this command?
Traceback (most recent call last):
File "d:/python/MADDPG/multiagent-particle-envs-master/bin/interactive.py", line 36, in
env.render()
File "d:\python\MADDPG\multiagent-particle-envs-master\bin..\multiagent\environment.py", line 261, in render
results.append(self.viewers[i].render(return_rgb_array = mode=='rgb_array'))
File "d:\python\MADDPG\multiagent-particle-envs-master\bin..\multiagent\rendering.py", line 89, in render
self.window.switch_to()
File "D:\python\Anaconda3\envs\python36\lib\site-packages\pyglet\window\win32_init_.py", line 305, in switch_to
self.context.set_current()
AttributeError: 'NoneType' object has no attribute 'set_current'