code: def bulk_get(cls, files, api=None):
          
          api = api or cls._API
          file_ids = [Transform.to_file(file_) for file_ in files]
          data = {'file_ids': file_ids}
  
          logger.info('Getting files in bulk.')
          response = api.post(url=cls._URL['bulk_get'], data=data)
          return FileBulkRecord.parse_records(response=response, api=api)
docs: Retrieve files with specified ids in bulk
          :param files: Files to be retrieved.
          :param api: Api instance.
          :return: List of FileBulkRecord objects.