title: Django admin list edit
body: <p>I encountered some weird behavior when using admin <code>list_editable</code> with a restricting custom manager. Each time I am trying to save list changes in admin, I get the message: <em>Please correct the errors below.</em> </p>
  
  <p>Any suggestions on how to get rid of this error message?</p>
  
  <p>Here is a minimal sample:</p>
  
  <p><strong>models.py</strong></p>
  
  <pre><code>from django.db import models
  
  class RestrictedManager(models.Manager):
      def get_queryset(self):
          return super(RestrictedManager, self).get_queryset().none()
  
  
  class MyModel(models.Model):
      on = models.BooleanField()
  
      objects = RestrictedManager()
      all_objects = models.Manager()
  </code></pre>
  
  <p><strong>admin.py</strong></p>
  
  <pre><code>from django.contrib.admin import ModelAdmin, site
  from models import MyModel
  
  class MyModelAdmin(ModelAdmin):
      list_editable = ('on',)
      list_display = ('id', 'on',)
  
      def get_queryset(self, request):
          return MyModel.all_objects
  
  site.register(MyModel, MyModelAdmin)
  </code></pre>
  
  <p>If you wonder, why am I using a <code>none()</code> default queryset, I don't. I used <code>none()</code> only to simplify the example. The issue occurs with any object filtered out by the default manager.</p>