train_django/mptt_test/models.py

from django.contrib.auth.models import User
from django.db import models
from django.db.models import Model
from mptt.models import MPTTModel, TreeForeignKey


# Create your models here.
class Genre(MPTTModel):
    name = models.CharField(max_length=50, unique=True)
    parent = TreeForeignKey('self', on_delete=models.CASCADE, null=True, blank=True, related_name='children')

    class MPTTMeta:
        order_insertion_by = ['name']