gunicorn py3
When install gunicorn with python3, e.g. pip3 install gunicorn, and run it
it still runs under python2 context somehow, so if the web app is using py3 libraries it would fail complaining about "not found module".
One way is to use python virtualenv, and run from there
Another way is to uninstall any gunicorn version from py2 or yum
pip uninstall gunicorn
or
yum uninstall gunicorn
Then install it again with py3
pip3 install gunicorn
Finally, need to run it with the abosolute path:
/usr/local/bin/gunicorn -b 0.0.0.0:8080 your_app:app