new_contents: # -*- coding: utf-8 -*-
  from __future__ import unicode_literals
  
  from django.db import models, migrations
  
  
  class Migration(migrations.Migration):
  
      dependencies = [
      ]
  
      operations = [
          migrations.CreateModel(
              name='Directory',
              fields=[
                  ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)),
                  ('name', models.CharField(max_length=255)),
              ],
              options={
              },
              bases=(models.Model,),
          ),
          migrations.CreateModel(
              name='Document',
              fields=[
                  ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)),
                  ('name', models.CharField(max_length=100)),
                  ('type', models.CharField(max_length=2, choices=[('v', 'video'), ('s', 'sound'), ('p', 'pdf'), ('i', 'image'), ('o', 'others')])),
                  ('description', models.CharField(max_length=250)),
              ],
              options={
              },
              bases=(models.Model,),
          ),
          migrations.CreateModel(
              name='SubDirRelation',
              fields=[
                  ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)),
                  ('child', models.ForeignKey(related_name='child', to='cntapp.Directory')),
                  ('parent', models.ForeignKey(related_name='parent', to='cntapp.Directory')),
              ],
              options={
              },
              bases=(models.Model,),
          ),
          migrations.AddField(
              model_name='directory',
              name='documents',
              field=models.ManyToManyField(to='cntapp.Document', blank=True),
              preserve_default=True,
          ),
          migrations.AddField(
              model_name='directory',
              name='sub_dirs',
              field=models.ManyToManyField(to='cntapp.Directory', through='cntapp.SubDirRelation', blank=True),
              preserve_default=True,
          ),
      ]
  
subject: add migration