Building the course models

Your e-learning platform will offer courses on various subjects. Each course will be divided into a configurable number of modules, and each module will contain a configurable number of contents. The contents will be of various types: text, file, image, or video. The following example shows what the data structure of your course catalog will look like:

Subject 1
  Course 1
    Module 1
      Content 1 (image)
      Content 2 (text)
    Module 2
      Content 3 (text)
      Content 4 (file)
      Content 5 (video)
      ...

Let's build the course models. Edit the models.py file of the courses application and add the following code to it:

from django.db import models
from django.contrib.auth.models import User
class Subject(models.Model):
    title = models.CharField(max_length=200)
    slug = models.SlugField(max_length=200, unique=True)
    class Meta:
        ordering = ['title']
    def __str__(self):
        return self.title...