Silence a few missing imports

Author: dmoisset

polls/admin.py

@@ -1,4 +1,4 @@
-from django.contrib import admin
+from django.contrib import admin  # type: ignore
 
 from .models import Question
 

polls/migrations/0001_initial.py

@@ -3,8 +3,8 @@
 from __future__ import unicode_literals
 from typing import Tuple, List
 
-from django.db import migrations, models
-import django.db.models.deletion
+from django.db import migrations, models  # type: ignore
+import django.db.models.deletion  # type: ignore
 
 
 class Migration(migrations.Migration):