Get ScreenShot Error under docker.

[lyyiangang]

Hi Sir,

When I run python3 main.py in docker, I get following errors.

root@2e21e243668f:~/project/deepeye/src# python main.py
Exception in thread Thread-1:
Traceback (most recent call last):
  File "/usr/lib/python3.5/threading.py", line 914, in _bootstrap_inner
    self.run()
  File "/usr/lib/python3.5/threading.py", line 862, in run
    self._target(*self._args, **self._kwargs)
  File "/root/project/deepeye/src/driving_assistant/user_interface/GUI.py", line 700, in mainLoop
    window_height = height)
  File "/root/project/deepeye/src/driving_assistant/DrivingAssistant.py", line 69, in __init__
    self.window_manager = mss.mss()
  File "/usr/local/lib/python3.5/dist-packages/mss/factory.py", line 38, in mss
    return MSS(**kwargs)
  File "/usr/local/lib/python3.5/dist-packages/mss/linux.py", line 209, in __init__
    raise ScreenShotError("No Xrandr extension found.")
mss.exception.ScreenShotError: No Xrandr extension found.