[common][serializers] Fix decoding handling for description

beat/web/common/serializers.py

@@ -257,7 +257,10 @@ class ContributionSerializer(VersionableSerializer):
         exclude = ['description_file', 'declaration_file']
 
     def get_description(self, obj):
-        return obj.description.decode('utf-8')
+        result = obj.description
+        if six.PY2:
+            result = result.decode('utf-8')
+        return result
 
     def get_declaration(self, obj):
         object_format = self.context.get('object_format')