docs: function parseError(res, body) {
    // Res is optional.
    if (body == null) {
      body = res;
    }
    // Status code is required.
    const status = parseError.findErrorCode(sliced(arguments));
    if (!status) {
      return false;
    }
    // Body can have an error-like object, in which case the attributes will be used.
    const obj = findErrorObj(body);
    if (obj) {
      body = Object.assign(body, obj);
    }
    return [status, body];
  }