new_contents: # -*- coding: utf-8 -*-
  # Generated by Django 1.11.15 on 2019-01-31 22:18
  from __future__ import unicode_literals
  
  from django.db import migrations, models
  import django.db.models.deletion
  
  
  class Migration(migrations.Migration):
  
      dependencies = [
          ('judge', '0084_contest_formats'),
      ]
  
      operations = [
          migrations.CreateModel(
              name='SubmissionSource',
              fields=[
                  ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
                  ('source', models.TextField(max_length=65536, verbose_name='source code')),
                  ('submission', models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, related_name='link', to='judge.Submission', verbose_name='associated submission')),
              ],
          ),
          migrations.RunSQL(
              ['''INSERT INTO judge_submissionsource (source, submission_id)
                  SELECT source, id AS 'submission_id' FROM judge_submission;'''],
              ['''UPDATE judge_submission sub
                  INNER JOIN judge_submissionsource src ON sub.id = src.submission_id
                  SET sub.source = src.source;'''],
              elidable=True
          ),
          migrations.RemoveField(
              model_name='submission',
              name='source',
          ),
          migrations.AlterField(
              model_name='submissionsource',
              name='submission',
              field=models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, related_name='source', to='judge.Submission', verbose_name='associated submission')
          ),
      ]
  
subject: Add migration; #872