code: func StringifyKey(key interface{}) string {
  	switch key {
  	// For named keys we want to handle explicitly
  
  	default:
  		// Stringify keys
  		switch k := key.(type) {
  		case string:
  			return k
  		case fmt.Stringer:
  			return k.String()
  		default:
  			return fmt.Sprintf("%v", key)
  		}
  	}
  }
docs: // Provides a canonical way to stringify keys