ImproperlyConfigured: You must either define the environment variable DJANGO_SETTINGS_MODULE or call settings.configure() before accessing settings

From The Definitive Guide to Django: Web Development Done Right:

If you’ve used Python before, you may be wondering why we’re running python manage.py shell instead of just python. Both commands will start the interactive interpreter, but the manage.py shell command has one key difference: before starting the interpreter, it tells Django which settings file to use.

Use Case: Many parts of Django, including the template system, rely on your settings, and you won’t be able to use them unless the framework knows which settings to use.

If you’re curious, here’s how it works behind the scenes. Django looks for an environment variable called DJANGO_SETTINGS_MODULE, which should be set to the import path of your settings.py. For example, DJANGO_SETTINGS_MODULE might be set to 'mysite.settings', assuming mysite is on your Python path.

When you run python manage.py shell, the command takes care of setting DJANGO_SETTINGS_MODULE for you.**

Create a .env file that will hold your credentials at the root of your project and leave it out of versioning:

$ echo ".env" >> .gitignore

In the .env file, add the variables (adapt them according to your installation):

$ echo "DJANGO_SETTINGS_MODULE=myproject.settings.production"> .env
#50 caracter random key
$ echo "SECRET_KEY='####'">> .env

To use them, put this on top of your production.py settings file:

import os

env = os.environ.copy()
SECRET_KEY = env['SECRET_KEY']

Publish it to Heroku using this gem: http://github.com/ddollar/heroku-config.git

$ heroku plugins:install git://github.com/ddollar/heroku-config.git
$ heroku config:push

This way you avoid to change virtualenv files.

*Based on this tutorial

Django needs your application-specific settings. Since it is already inside your manage.py, just use that. The faster, but perhaps temporary, solution is:

python manage.py shell

If you are using the local server, run Django shell using python manage.py shell. It will take you to the Django python environment and you are good to go.

In my case it was the use of the call_command module that posed a problem.
I added set DJANGO_SETTINGS_MODULE=mysite.settings but it didn’t work.

I finally found it:

add these lines at the top of the script, and the order matters.

import os
os.environ.setdefault("DJANGO_SETTINGS_MODULE", "mysite.settings")

import django
django.setup()

from django.core.management import call_command

In my case, it was a Python path issue.

1. First set your PYTHONPATH
2. then set DJANGO_SETTINGS_MODULE
3. then run django-admin shell command (django-admin dbshell)

(venv) shakeel@workstation:~/project_path$ export PYTHONPATH=/home/shakeel/project_path
(venv) shakeel@workstation:~/project_path$ export DJANGO_SETTINGS_MODULE=my_project.settings
(venv) shakeel@workstation:~/project_path$ django-admin dbshell
SQLite version 3.22.0 2018-01-22 18:45:57
Enter ".help" for usage hints.
sqlite>

otherwise python manage.py shell works like charm.

I found this error when I set in admin.py my list_display = ('name',) I changed it to list_display = ('name','date') And it worked.

If you are here due to error while trying to run daphne on server then here is the answer for you .

Change you asgi.py file like this.

import os
from django.conf.urls import url

os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'mc_backend.settings')

from channels.routing import ProtocolTypeRouter, URLRouter
from django.core.asgi import get_asgi_application
django_asgi_app = get_asgi_application()

from channels.auth import AuthMiddlewareStack   
import api_backend.routing


application = ProtocolTypeRouter({
    "http": django_asgi_app,
    'websocket': AuthMiddlewareStack(
        URLRouter(
            api_backend.routing.websocket_urlpatterns
        )
    )
})

I have used pipenv to manage virtual environment for django project.

SOLUTION

1. pipenv shell
2. python manage.py shell

I had a wrong way of import.

First I imported models of django without (before I declare that the file use django)

import pika, json, os, django
from products.models import Product

os.environ.setdefault("DJANGO_SETTINGS_MODULE", "admin.settings")
django.setup()

But then I changed the import as below and it works (basically declaring file uses django and then importing models and other apps)

import pika, json, os, django

os.environ.setdefault("DJANGO_SETTINGS_MODULE", "admin.settings")
django.setup()

from products.models import Product

I’ve got this error while trying to import models from python console. My workaround:

import os, django
os.environ.setdefault("DJANGO_SETTINGS_MODULE", "my_app.settings")
django.setup()

my_app.settings is path to your settings.py

And then you can import your models:

from users.models import UserModel

For me I just had to introduce the missing variables through "Preferences" => "Terminal" => "Environment variables":

1. Go to "Preferences" (cmd + ,)
2. Go Terminal and add two Environment
   variables (PYTHONPATH and DJANGO_SETTINGS_MODULE)

PYTHONPATH pointed to absolute path of the project root.
DJANGO_SETTINGS_MODULE pointed to the settings file name (relative to root path and without .py)

Please see attached picture.