code: public function error($error, $defaultStatusCode = null, array $headers = [])
      {
          if (is_string($error)) {
              $error = $this->api->getErrors()->error($error);
          } else if (is_array($error)) {
              $error = Error::create($error);
          }
  
          if (!$error instanceof ErrorInterface) {
              throw new \InvalidArgumentException('Expecting a string, array or error object.');
          }
  
          return $this->errors($error, $defaultStatusCode, $headers);
      }
docs: Create a response containing a single error.
  
  @param string|array|ErrorInterface $error
  @param int|null $defaultStatusCode
  @param array $headers
  @return mixed