Store the defended solution in the passage

apps/participation/migrations/0010_passage_solution_number.py

@@ -0,0 +1,19 @@
+# Generated by Django 3.0.11 on 2021-01-14 13:53
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('participation', '0009_auto_20210114_1313'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='passage',
+            name='solution_number',
+            field=models.PositiveSmallIntegerField(choices=[(1, 'Problem #1'), (2, 'Problem #2'), (3, 'Problem #3'), (4, 'Problem #4'), (5, 'Problem #5'), (6, 'Problem #6'), (7, 'Problem #7'), (8, 'Problem #8')], default=None, verbose_name='defended solution'),
+            preserve_default=False,
+        ),
+    ]