fix plus mixin for rest_framework 3.0
diff --git a/planetstack/core/xoslib/methods/sliceplus.py b/planetstack/core/xoslib/methods/sliceplus.py
index fffd997..b302aec 100644
--- a/planetstack/core/xoslib/methods/sliceplus.py
+++ b/planetstack/core/xoslib/methods/sliceplus.py
@@ -9,7 +9,7 @@
from plus import PlusSerializerMixin
class SlicePlusIdSerializer(serializers.ModelSerializer, PlusSerializerMixin):
- id = serializers.Field()
+ id = serializers.ReadOnlyField()
sliceInfo = serializers.SerializerMethodField("getSliceInfo")
humanReadableName = serializers.SerializerMethodField("getHumanReadableName")