func ToIDHeader(v string) string {
	v = url.QueryEscape(v)
	return "<" + strings.Replace(v, "%40", "@", -1) + ">"
}
func ToIDHeader(v string) string {
	v = url.QueryEscape(v)
	return "<" + strings.Replace(v, "%40", "@", -1) + ">"
}
func ToIDHeader ( v string ) string { v = url . QueryEscape ( v ) return " " + strings . Replace ( v , " " , " " , - 1 ) + " " }
// ToIDHeader encodes a Content-ID or Message-ID header value (RFC 2392) from a utf-8 string.
ToIDHeader encodes a Content - ID or Message - ID header value ( RFC 2392 ) from a utf - 8 string .