package errors type UnknownError struct { Err error } func (err UnknownError) Error() string { return err.Err.Error() } func (err UnknownError) Unwrap() error { return err.Err } type NotFoundError struct { Message string } func (err NotFoundError) Error() string { return err.Message } type AlreadyExistsError struct { Message string } func (err AlreadyExistsError) Error() string { return err.Message }