I have the following code:
models.py
    from django.db import models
    class Title(models.Model):
        title_name = models.CharField(max_length=200)
        category = models.CharField(max_length= 30)
    class Tags(models.Model):
        tag1 = models.CharField(max_length=15)
        tag2 = models.CharField(max_length=15)
        tag3 = models.CharField(max_length=15)
        tag4 = models.CharField(max_length=15)
    class Videos:
        primo: str
views.py
    from django.shortcuts import render, HttpResponse
    from django.http import HttpResponse
    from .models import Videos
    def home(request):
        vid = Videos()
        vid.primo = 'https://www.youtube.com/'
        return render(request, 'index.html', {'vid': vid})
settings.py
    INSTALLED_APPS = [
        'django.contrib.admin',
        'django.contrib.auth',
        'django.contrib.contenttypes',
        'django.contrib.sessions',
        'django.contrib.messages',
        'django.contrib.staticfiles',
    ]
When I run the server I get: RuntimeError: Model class home.models.Title doesn't declare an explicit app_label and isn't in an application in INSTALLED_APPS.
Everything was working before adding class Videos() and just using:
    def home(request):
        return render(request, 'index.html')
I don't understand what I should specify in the INSTALLED_APPS as I just added a new def to render a video URL inside my HTML. Why I get this error?
Thanks!