old_contents: # Generated by Django 2.2.17 on 2021-03-10 19:38
  
  from django.db import migrations, models
  import django.db.models.deletion
  
  
  class Migration(migrations.Migration):
  
      dependencies = [
          ('workshops', '0234_auto_20210228_0940'),
      ]
  
      operations = [
          migrations.RemoveField(
              model_name='event',
              name='sponsors',
          ),
          migrations.AddField(
              model_name='event',
              name='sponsor',
              field=models.ForeignKey(blank=False, help_text='Institution that is funding or organising the workshop.', null=True, on_delete=django.db.models.deletion.PROTECT, related_name='sponsored_events', to='workshops.Organization'),
          ),
          migrations.AlterField(
              model_name='event',
              name='administrator',
              field=models.ForeignKey(blank=False, help_text='Lesson Program administered for this workshop.', null=True, on_delete=django.db.models.deletion.PROTECT, related_name='administered_events', to='workshops.Organization'),
          ),
          migrations.AlterField(
              model_name='event',
              name='host',
              field=models.ForeignKey(help_text='Organisation hosting the event.', on_delete=django.db.models.deletion.PROTECT, related_name='hosted_events', to='workshops.Organization'),
          ),
          migrations.DeleteModel(
              name='Sponsorship',
          ),
      ]
  
new_contents: # Generated by Django 2.2.17 on 2021-03-10 19:38
  
  from django.db import migrations, models
  import django.db.models.deletion
  
  
  def create_event_host_to_sponsor(apps, schema_editor):
      """Copy event.host to event.sponsor for existing events."""
      Event = apps.get_model("workshops", "Event")
      Event.objects.exclude(host__isnull=True).update(sponsor=models.F('host'))
  
  
  class Migration(migrations.Migration):
  
      dependencies = [
          ('workshops', '0234_auto_20210228_0940'),
      ]
  
      operations = [
          migrations.RemoveField(
              model_name='event',
              name='sponsors',
          ),
          migrations.AddField(
              model_name='event',
              name='sponsor',
              field=models.ForeignKey(blank=False, help_text='Institution that is funding or organising the workshop.', null=True, on_delete=django.db.models.deletion.PROTECT, related_name='sponsored_events', to='workshops.Organization'),
          ),
          migrations.RunPython(create_event_host_to_sponsor, migrations.RunPython.noop),
          migrations.AlterField(
              model_name='event',
              name='administrator',
              field=models.ForeignKey(blank=False, help_text='Lesson Program administered for this workshop.', null=True, on_delete=django.db.models.deletion.PROTECT, related_name='administered_events', to='workshops.Organization'),
          ),
          migrations.AlterField(
              model_name='event',
              name='host',
              field=models.ForeignKey(help_text='Organisation hosting the event.', on_delete=django.db.models.deletion.PROTECT, related_name='hosted_events', to='workshops.Organization'),
          ),
          migrations.DeleteModel(
              name='Sponsorship',
          ),
      ]
  
subject: Add data migration for event.sponsor