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@xeroc

Collecting websockets==2.0 (from -r requirements-web.txt (line 37))
  Using cached websockets-2.0.tar.gz
    Complete output from command python setup.py egg_info:
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/private/var/folders/v2/9vnp2_3x5pv2ncqhlnc3vg9c0000gn/T/pip-build-FNNORu/websockets/setup.py", line 17, in <module>
        with open(os.path.join(root, 'README'), encoding='utf-8') as f:
    TypeError: 'encoding' is an invalid keyword argument for this function
    
    ----------------------------------------
Command "python setup.py egg_info" failed with error code 1 in /private/var/folders/v2/9vnp2_3x5pv2ncqhlnc3vg9c0000gn/T/pip-build-FNNORu/websockets/

hit me that error in the last command

you need to use python 3 and cannot use python2. I should probably add a check for the version somewhere