Does not work with python 3.7

[miyakogi]

Pyppeteer does not work with python 3.7 now, since current websockets module on PyPI does not work with python 3.7.

This problem is already fixed in github's master branch of websockets module, but it's not released yet.
If you want to use pyppeteer with python3.7 soon, use websockets module on github until it is released to PyPI.

pip install -U git+https://github.com/aaugustin/websockets

[miyakogi]

Websockets Version 6.0 which supports python 3.7 is now available on PyPI.