Installing Flask

# Ubuntu 16.04 (default Python 3.5), not Ubuntu => go install
sudo apt-get install software-properties-common
sudo apt-add-repository universe
sudo apt-get update
sudo apt-get install python-pip python3-dev python3-venv
# Environnements folders
mkdir venvs
# Specify the system python3 installation
python3 -m venv venvs/flaskproj
# Activate the virtualenv
source ~/venvs/flaskproj/bin/activate
pip install flask gunicorn

# Install Ngnix 
sudo apt install nginx
sudo ufw allow 'Nginx HTTP'
systemctl status nginx