if strings.Contains(err.String(), "can't find") {
		return r, errors.New(err.String())
	}
	return r, nil
}

func nslookupMX(name string) (mx []*MX, err error) {
	var r string
	if r, err = nslookup("mx", name); err != nil {
		return
	}
	mx = make([]*MX, 0, 10)
	// linux nslookup syntax
	// golang.org      mail exchanger = 2 alt1.aspmx.l.google.com.

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