text: Title: [FEATURE] Change _parse_presort_exp from a private function to public
  Body: **Context**
  Add any other context or screenshots about the feature request here.
  
  _parse_presort_exp was originally just used by the `partition` method. We are starting to use it in other places like the latest `limit` method of the execution engine. We will start to reuse this method more so we should just make it public.
  
  