Upgrade Python to 3.x

MacOS

brew install python

Installing Python 3 on Mac OS X: https://docs.python-guide.org/starting/install3/osx/

CentOS

yum install -y python36 python36-devel
rm /usr/bin/python /usr/bin/python-config /usr/bin/pip
ln -s /usr/bin/python3 /usr/bin/python
ln -s /usr/bin/python3-config /usr/bin/python-config
ln -s /usr/bin/pip3 /usr/bin/pip
mv /usr/bin/pydoc /usr/bin/pydoc2
ln -s /usr/bin/pydoc3.6 /usr/bin/pydoc