BOM-804

python3 compatibility
we only need to decode if the xml is bytes

common/lib/xmodule/xmodule/modulestore/xml.py

@@ -119,7 +119,7 @@ class ImportSystem(XMLParsingSystem, MakoDescriptorSystem):
                         orig_name = orig_name[len(tag) + 1:-12]
                     # append the hash of the content--the first 12 bytes should be plenty.
                     orig_name = "_" + orig_name if orig_name not in (None, "") else ""
-                    xml_bytes = xml.encode('utf8')
+                    xml_bytes = xml if isinstance(xml, bytes) else xml.encode('utf-8')
                     return tag + orig_name + "_" + hashlib.sha1(xml_bytes).hexdigest()[:12]
 
                 # Fallback if there was nothing we could use: