code: def _prepare_edit(self, record):
          
          data = record.dumps()
          # Keep current record revision for merging.
          data['_deposit']['pid']['revision_id'] = record.revision_id
          data['_deposit']['status'] = 'draft'
          data['$schema'] = self.build_deposit_schema(record)
          return data
docs: Update selected keys.
  
          :param record: The record to prepare.