Simple "Hello world" application

Start a project:
$ django-admin startproject lecture3
Change directory into the folder "lecture3:
$ cd lecture3
Run the webserver then navigate to http://localhost:8000 to check that it is working
$ python manage.py runserver
Create a simple app called "hello"
$ python manage.py startapp hello
This will create a folder called "hello" containing a variety of files
In the lecture3 folder edit the settings.py file and add the hello app to the configuration

INSTALLED_APPS = [
    'hello',
    'django.contrib.admin'

In the hello folder edit the views.py file
At the top of the file add "from django.http import HttpResponse"
Then add

 def index(request):
       return HttpResponse("Hello World")

Again in the "hello" folder create a urls.py file with the following contents:

    from django.urls import path
    from . import views
    urlpatterns={
        path("", views.index, name="index")
    }

In the lecture3 directory edit the urls.py file and add "include" to the import line, then add:

path('hello/', include("hello.urls"))

so that the urls.py file in the lecture3 directory now looks like:

from django.contrib import admin
from django.urls import path, include
 
urlpatterns = [
    path('admin/', admin.site.urls),
    path('hello/', include("hello.urls"))
]