added utc compat to fields

rest_framework/fields.py

@@ -32,7 +32,7 @@ from django.utils.translation import ugettext_lazy as _
 
 from rest_framework import ISO_8601
 from rest_framework.compat import (
-    get_remote_field, unicode_repr, unicode_to_repr, value_from_object
+    get_remote_field, unicode_repr, unicode_to_repr, value_from_object, utc
 )
 from rest_framework.exceptions import ErrorDetail, ValidationError
 from rest_framework.settings import api_settings
@@ -1104,7 +1104,7 @@ class DateTimeField(Field):
         if (field_timezone is not None) and not timezone.is_aware(value):
             return timezone.make_aware(value, field_timezone)
         elif (field_timezone is None) and timezone.is_aware(value):
-            return timezone.make_naive(value, timezone.UTC())
+            return timezone.make_naive(value, utc)
         return value
 
     def default_timezone(self):