func VersionSeries(version string) (string, error) {
	if version == "" {
		return "", errors.Trace(unknownVersionSeriesError(""))
	}
	seriesVersionsMutex.Lock()
	defer seriesVersionsMutex.Unlock()
	if ser, ok := versionSeries[version]; ok {
		return ser, nil
	}
	updateSeriesVersionsOnce()
	if ser, ok := versionSeries[version]; ok {
		return ser, nil
	}
	return "", errors.Trace(unknownVersionSeriesError(version))
}
// VersionSeries returns the series (e.g.trusty) for the specified version (e.g. 14.04).
VersionSeries returns the series  for the specified version .
// VersionSeries returns the series ( e . g . trusty ) for the specified version ( e . g . 14 . 04 ) .
func VersionSeries(version string) (string, error) {
	if version == "" {
		return "", errors.Trace(unknownVersionSeriesError(""))
	}
	seriesVersionsMutex.Lock()
	defer seriesVersionsMutex.Unlock()
	if ser, ok := versionSeries[version]; ok {
		return ser, nil
	}
	updateSeriesVersionsOnce()
	if ser, ok := versionSeries[version]; ok {
		return ser, nil
	}
	return "", errors.Trace(unknownVersionSeriesError(version))
}
func VersionSeries ( version string ) ( string , error ) { if version == " " { return " " , errors . Trace ( unknownVersionSeriesError ( " " ) ) } seriesVersionsMutex . Lock ( ) defer seriesVersionsMutex . Unlock ( ) if ser , ok := versionSeries [ version ] ; ok { return ser , nil } updateSeriesVersionsOnce ( ) if ser , ok := versionSeries [ version ] ; ok { return ser , nil } return " " , errors . Trace ( unknownVersionSeriesError ( version ) ) }
VersionSeries returns the series  for the specified version .
VersionSeries returns the series for the specified version .