code: func AddFeatureGatesStringFlag(fs *pflag.FlagSet, featureGatesString *string) {
  	if knownFeatures := features.KnownFeatures(&features.InitFeatureGates); len(knownFeatures) > 0 {
  		fs.StringVar(featureGatesString, FeatureGatesString, *featureGatesString, "A set of key=value pairs that describe feature gates for various features. "+
  			"Options are:\n"+strings.Join(knownFeatures, "\n"))
  	} else {
  		fs.StringVar(featureGatesString, FeatureGatesString, *featureGatesString, "A set of key=value pairs that describe feature gates for various features. "+
  			"No feature gates are available in this release.")
  	}
  }
docs: // AddFeatureGatesStringFlag adds the --feature-gates flag to the given flagset