Why are you making a new method v calling ```
module = modulestore().create_and_save_xmodule(loc, definition_data=data_content)
# if necessary, but I don't think it is. data_dir is only used by the xml modulestore and should go away
module.data_dir = course_dir
```? 
create and save, btw, handles the static tab logic. I'm replacing it w/ mixed modulestore.create_item(..)
if data_content has both metadata and data, then you can either split them into the separate args or use the new version I've made in dhm/mixed_ms_converter to pass fields={} to create_and_save which doesn't segregate metadata from data, just takes a dict of field names and values.