code: def _update_uncompressed(collection_name, upsert, multi, spec,
                           doc, safe, last_error_args, check_keys, opts):
      
      op_update, max_bson_size = _update(
          collection_name, upsert, multi, spec, doc, check_keys, opts)
      rid, msg = __pack_message(2001, op_update)
      if safe:
          rid, gle, _ = __last_error(collection_name, last_error_args)
          return rid, msg + gle, max_bson_size
      return rid, msg, max_bson_size
docs: Internal update message helper.