Hi,
I want to run the pytorch-a3c example 10 with env = PongDeterministic-v4. I’ve had gym, gym[atari], atari-py installed by pip3. And the following codes:
[who@localhost pytorch-a3c]$ python3
Python 3.7.7 (default, Mar 13 2020, 21:39:43) 
[GCC 9.2.1 20190827 (Red Hat 9.2.1-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from gym import envs
>>> env_names = [spec.id for spec in envs.registry.all()]
>>> for name in sorted(env_names):
...     print(name)
... 


has had the env listed:
Pong-ram-v0
Pong-ram-v4
Pong-ramDeterministic-v0
Pong-ramDeterministic-v4
Pong-ramNoFrameskip-v0
Pong-ramNoFrameskip-v4
Pong-v0
Pong-v4
PongDeterministic-v0
PongDeterministic-v4
PongNoFrameskip-v0
PongNoFrameskip-v4


I have run the project as its Usage recommended as:
python3 main.py --env-name "PongDeterministic-v4" --num-processes 16

and encountered following exception:
Process Process-1:
Traceback (most recent call last):
  File "/usr/lib64/python3.7/multiprocessing/process.py", line 297, in _bootstrap
    self.run()
  File "/usr/lib64/python3.7/multiprocessing/process.py", line 99, in run
    self._target(*self._args, **self._kwargs)
  File "/home/zf/workspaces/workspace_python/pytorch-a3c/test.py", line 21, in test
    state = env.reset()
  File "/home/zf/.local/lib/python3.7/site-packages/gym/core.py", line 257, in reset
    observation = self.env.reset(**kwargs)
  File "/home/zf/.local/lib/python3.7/site-packages/gym/core.py", line 258, in reset
    return self.observation(observation)
  File "/home/zf/.local/lib/python3.7/site-packages/gym/core.py", line 265, in observation
    raise NotImplementedError
NotImplementedError


And the command for env = Tennis-ram-v0 also failed with the same exception.
I am not experienced in python environment. Would you please hint the possible solutions?