3 files changed, 14 insertions, 2 deletions
diff --git a/django/contrib/gis/db/models/sql/aggregates.py b/django/contrib/gis/db/models/sql/aggregates.py
index f8f3ed1eb4..c0a7d894eb 100644
--- a/django/contrib/gis/db/models/sql/aggregates.py
+++ b/django/contrib/gis/db/models/sql/aggregates.py
@@ -1,7 +1,11 @@
-from django.db.models.sql.aggregates import Aggregate
+from django.db.models.sql import aggregates
+from django.db.models.sql.aggregates import *  # NOQA
 from django.contrib.gis.db.models.fields import GeometryField
 
 
+__all__ = ['Collect', 'Extent', 'Extent3D', 'MakeLine', 'Union'] + aggregates.__all__
+
+
 class GeoAggregate(Aggregate):
     # Default SQL template for spatial aggregates.
     sql_template = '%(function)s(%(field)s)'
diff --git a/django/db/models/sql/aggregates.py b/django/db/models/sql/aggregates.py
index 0e1794e0a9..8542a330c6 100644
--- a/django/db/models/sql/aggregates.py
+++ b/django/db/models/sql/aggregates.py
@@ -5,6 +5,10 @@ import copy
 
 from django.db.models.fields import IntegerField, FloatField
 
+
+__all__ = ['Aggregate', 'Avg', 'Count', 'Max', 'Min', 'StdDev', 'Sum', 'Variance']
+
+
 # Fake fields used to identify aggregate types in data-conversion operations.
 ordinal_aggregate_field = IntegerField()
 computed_aggregate_field = FloatField()
diff --git a/django/forms/models.py b/django/forms/models.py
index 71da43390c..32f0f043ae 100644
--- a/django/forms/models.py
+++ b/django/forms/models.py
@@ -134,7 +134,11 @@ def model_to_dict(instance, fields=None, exclude=None):
                 data[f.name] = []
             else:
                 # MultipleChoiceWidget needs a list of pks, not object instances.
-                data[f.name] = list(f.value_from_object(instance).values_list('pk', flat=True))
+                qs = f.value_from_object(instance)
+                if qs._result_cache is not None:
+                    data[f.name] = [item.pk for item in qs]
+                else:
+                    data[f.name] = list(qs.values_list('pk', flat=True))
         else:
             data[f.name] = f.value_from_object(instance)
     return data