refactor: move themes to admin question

Resolves #95

people/migrations/0044_themes_to_admin_question.py

@@ -0,0 +1,39 @@
+# Generated by Django 2.2.10 on 2021-03-10 09:05
+
+from django.db import migrations
+
+from .utils.question_sets import port_question
+
+
+def migrate_forward(apps, schema_editor):
+    # Make question
+    Theme = apps.get_model('people', 'Theme')
+    theme_question = port_question(
+        apps, 'Research theme affiliation',
+        Theme.objects.all().values_list('name', flat=True),
+        is_multiple_choice=True)
+
+    PersonAnswerSet = apps.get_model('people', 'PersonAnswerSet')
+    for answerset in PersonAnswerSet.objects.all():
+        for theme in answerset.themes.all():
+            answerset.question_answers.add(
+                theme_question.answers.get(text=theme.name)
+            )
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('people', '0043_organisationanswerset_is_partner_organisation'),
+    ]
+
+    operations = [
+        migrations.RunPython(migrate_forward),
+        migrations.RemoveField(
+            model_name='personanswerset',
+            name='themes',
+        ),
+        migrations.DeleteModel(
+            name='Theme',
+        ),
+    ]