Django

Source: djangoproject.com

Installing

Installation:

sudo pip3 install django

Check installed version:

python3 -m django --version

Creating project

cd  /home/mycode (Do not put code under /var/www)
django-admin startproject mysite 

Avoid using names like django (conflict with Django itself) or test (conflicts with a built-in Python package)

Startproject command will create:

mysite/
    manage.py
    mysite/
        __init__.py
        settings.py
        urls.py
        wsgi.py

These files are:

• The outer mysite/: Just a container for the project. It can be renamed it to anything.
• manage.py: Command-line utility that allows to interact with this Django project in various ways.
• The inner mysite/ directory is the actual Python package for the project. This is the Python package name to use to import anything inside it (e.g. mysite.urls).
• mysite/__init__.py: Empty file that tells Python that this directory should be considered a Python package.
• mysite/settings.py: Settings/configuration for this Django project.
• mysite/urls.py: The URL declarations for this Django project; a “table of contents” of your Django-powered site.
• mysite/wsgi.py: An entry-point for WSGI-compatible web servers to serve your project.

Running Project

python manage.py runserver
http://127.0.0.1:8000/

Changing the port

python manage.py runserver 8080

Listen on all available public IPs:

python manage.py runserver 0:8000
python manage.py runserver 0.0.0.0:8000

Automatic reloading of runserver:

The server automatically reloads Python code for each request as needed.
No need to restart the server for code changes to take effect. 
Some actions like adding files don’t trigger a restart, need to restart the server in these cases.

Invalid http_host header

Need to add 198.211.99.20 to ALLOWED_HOSTS setting in project settings.py file
ALLOWED_HOSTS = ['198.211.99.20', 'localhost', '127.0.0.1']