How to upgrade virtualenv (virtual environment) to Python 3.7 on Ubuntu ( Ubuntu server 18.04 )

Thanks for this great tutorial. Does anyone have similar instructions for CentOS or a similar rpm-based linux? I previously posted about the problem with deprecating Python 3.6 for CentOS, as there are no officially supported 3.7+ packages available yet, but no one has commented yet (see Python support on CentOS after version 3.6 deprecation).