defer import for Django 1.11

Author: sheppard

data_wizard/idmap.py

@@ -1,11 +1,10 @@
-from rest_framework.serializers import ValidationError
-
-
 def never(value, field):
     return None
 
 
 def existing(value, field):
+    # FIXME: Move import to top when dropping Django 1.11
+    from rest_framework.serializers import ValidationError
     try:
         field.to_internal_value(value)
     except ValidationError:

tests/data_app/wizard.py

@@ -48,6 +48,7 @@ class Meta:
         model = FKModel
         fields = "__all__"
 
+
 class SlugMapExistingSerializer(SlugSerializer):
     class Meta(SlugSerializer.Meta):
         data_wizard = {