code: def attachment_both(self, files, parentid=None):
          
          orig = self._attachment_template("imported_file")
          to_add = [orig.copy() for f in files]
          for idx, tmplt in enumerate(to_add):
              tmplt["title"] = files[idx][0]
              tmplt["filename"] = files[idx][1]
          if parentid:
              return self._attachment(to_add, parentid)
          else:
              return self._attachment(to_add)
docs: Add child attachments using title, filename
          Arguments:
          One or more lists or tuples containing title, file path
          An optional Item ID, which will create child attachments