Django - Reverse for 'index' not found. 'index' is not a valid view function or pattern name

I am new to Django. I have been working based on the template from Mozilla: https://developer.mozilla.org/en-US/docs/Learn/Server-side/Django/Tutorial_local_library_website

I have created a project called 'debtSettler'. And it has an app called 'home'.

I have the following url mappings:

./debtSettler/debtSettler/urls.py:

urlpatterns = [
   
    path('home/', include('home.urls')),    
    path('admin/', admin.site.urls),
    path('', RedirectView.as_view(url='home/')),    
] + static(settings.STATIC_URL, document_root=settings.STATIC_ROOT)

./debtSettler/home/urls.py:

app_name = 'home'
urlpatterns = [    
    path('', views.index, name='index'),
    path('clubs/', views.ClubListView.as_view(), name='clubs'),    
]

And views:

./debtSettler/home/views.py:

from django.http import HttpResponse, HttpResponseRedirect


def index(request):

    num_clubs = Club.objects.all().count()    

   
    # The 'all()' is implied by default.
    num_members = Member.objects.count()

    context = {
        'num_clubs': num_clubs,
        'num_members': num_members,        
    }

    # Render the HTML template index.html with the data in the context variable
    return render(request, 'index.html', context=context)

class ClubListView(generic.ListView):

    model = Club

    def get_context_data(self, **kwargs):
        # Call the base implementation first to get the context
        context = super(ClubListView, self).get_context_data(**kwargs)
        # Create any data and add it to the context
        context['some_data'] = 'This is just some data'
        return context

In the template, I have two urls that give the error:

<a href=" {% url 'index' %}  ">Home</a>
<a href=" {% url 'clubs' %} ">All clubs</a>

Reverse for 'index' not found. 'index' is not a valid view function or pattern name.

If I add the my_app:my_view, it works as expected:

Home All clubs

but I plan to do more of the url mapping further in the app so I want to understand what I am doing wrong with the url. It seems to me like I am doing things very similar to the tutorial.

try to add "home:" before'index'

try this:

<a href=" {% url 'home:index' %}  ">Home</a>
<a href=" {% url 'home:clubs' %} ">All clubs</a>

And you should add namespace

urlpatterns = [
   
    path('home/', include('home.urls','home'),namespace = 'home'),    
    path('admin/', admin.site.urls),
    path('', RedirectView.as_view(url='home/')),    
] + static(settings.STATIC_URL, document_root=settings.STATIC_ROOT)

You used an app_name, so then the view names are "namespace" with:

<a href="{% url 'home:index' %}">Home</a>
<a href="{% url 'home:clubs' %}">All clubs</a>
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