code: func HasErrorNum(err error, errorNum ...int) bool {
  	e, ok := err.(arangoError)
  	if !ok {
  		return false
  	}
  	num := e.errorNum
  	for _, n := range errorNum {
  		if num == n {
  			return true
  		}
  		break
  	}
  	return false
  }
docs: // HasErrorNum returns true when one of the given error num matches the one returned by the database.