title: Django set autofield value in bulk_create
body: <p>I'm trying to bulk_create a lot of records in a new table in my PostgresQL db.</p>
  
  <p>The primary key on the table is an AutoField called <code>id</code>.</p>
  
  <p>As of Django 1.10 (which I'm using), this should work in Postgres: <a href="https://docs.djangoproject.com/en/1.10/ref/models/querysets/#bulk-create" rel="nofollow noreferrer">https://docs.djangoproject.com/en/1.10/ref/models/querysets/#bulk-create</a></p>
  
  <p>However, the bulk_create is failing with the following error.<br>
  <code>django.db.utils.IntegrityError: null value in column "id" violates not-null constraint</code></p>
  
  <p>Which suggests that the <code>id</code> field isn't automatically assigned a value.</p>
  
  <p>Does anyone know how to resolve this?</p>