Make SessionKeyValueStore variable names clearer

cms/djangoapps/contentstore/views/session_kv_store.py

@@ -2,27 +2,27 @@ from xblock.runtime import KeyValueStore, InvalidScopeError
 
 
 class SessionKeyValueStore(KeyValueStore):
-    def __init__(self, request, model_data):
-        self._model_data = model_data
+    def __init__(self, request, descriptor_model_data):
+        self._descriptor_model_data = descriptor_model_data
         self._session = request.session
 
     def get(self, key):
         try:
-            return self._model_data[key.field_name]
+            return self._descriptor_model_data[key.field_name]
         except (KeyError, InvalidScopeError):
             return self._session[tuple(key)]
 
     def set(self, key, value):
         try:
-            self._model_data[key.field_name] = value
+            self._descriptor_model_data[key.field_name] = value
         except (KeyError, InvalidScopeError):
             self._session[tuple(key)] = value
 
     def delete(self, key):
         try:
-            del self._model_data[key.field_name]
+            del self._descriptor_model_data[key.field_name]
         except (KeyError, InvalidScopeError):
             del self._session[tuple(key)]
 
     def has(self, key):
-        return key in self._model_data or key in self._session
+        return key in self._descriptor_model_data or key in self._session