Better fix for MentoringBlock attributes saving.

mentoring/light_children.py

@@ -127,7 +127,7 @@ class LightChildrenMixin(XBlockWithChildrenFragmentsMixin):
             return
 
         node = etree.parse(StringIO(self.xml_content)).getroot()
-        LightChildrenMixin.init_block_from_node(self, node, {})
+        LightChildrenMixin.init_block_from_node(self, node, node.items())
 
     def get_children_objects(self):
         """

mentoring/mentoring.py

@@ -179,7 +179,7 @@ class MentoringBlock(XBlockWithLightChildren):
 
         xml_content = submissions['xml_content']
         try:
-            xml = etree.parse(StringIO(xml_content))
+            etree.parse(StringIO(xml_content))
         except etree.XMLSyntaxError as e:
             response = {
                 'result': 'error',
@@ -191,14 +191,6 @@ class MentoringBlock(XBlockWithLightChildren):
             }
             self.xml_content = xml_content
 
-        try:
-            self.url_name = xml.getroot().attrib['url_name']
-        except KeyError as e:
-            response = {
-                'result': 'error',
-                'message': 'mentoring "url_name" attribute is missing'
-            }
-
         log.debug(u'Response from Studio: {}'.format(response))
         return response