Change of model manager when makemigrations in Django 1.10

lms/djangoapps/certificates/migrations/0013_change_eligible_certs_manager.py

+# -*- coding: utf-8 -*-
+# Generated by Django 1.10.8 on 2017-12-04 18:24
+from __future__ import unicode_literals
+
+from django.db import migrations
+import django.db.models.manager
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('certificates', '0012_certificategenerationcoursesetting_include_hours_of_effort'),
+    ]
+
+    operations = [
+        migrations.AlterModelManagers(
+            name='generatedcertificate',
+            managers=[
+                ('eligible_certificates', django.db.models.manager.Manager()),
+            ],
+        ),
+    ]