add migration for student website url

core/migrations/0021_student_website_url.py

+# -*- coding: utf-8 -*-
+# Generated by Django 1.10.5 on 2019-10-06 08:12
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0020_merge_20191006_1444'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='student',
+            name='website_url',
+            field=models.URLField(blank=True, null=True),
+        ),
+    ]