code: func (b *BigIP) checkError(resp []byte) error {
  	if len(resp) == 0 {
  		return nil
  	}
  
  	var reqError RequestError
  
  	err := json.Unmarshal(resp, &reqError)
  	if err != nil {
  		return errors.New(fmt.Sprintf("%s\n%s", err.Error(), string(resp[:])))
  	}
  
  	err = reqError.Error()
  	if err != nil {
  		return err
  	}
  
  	return nil
  }
docs: // checkError handles any errors we get from our API requests. It returns either the
  // message of the error, if any, or nil.