added a common.MultiLevelAttributeError to copying, because there were some problems

jedi/evaluate.py

@@ -649,6 +649,7 @@ class Execution(Executable):
         objects can be used for the executions, as if they were in the
         execution.
         """
+        try:
             # Copy all these lists into this local function.
             attr = getattr(self.base, prop)
             objects = []
@@ -662,6 +663,8 @@ class Execution(Executable):
                         copied = Function(copied)
                 objects.append(copied)
             return objects
+        except AttributeError:
+            raise common.MultiLevelAttributeError(sys.exc_info())
 
     def __getattr__(self, name):
         if name not in ['start_pos', 'end_pos', 'imports']: